DIY bp gurus: will I need to corn my black powder? for use in cartrides?
Retrieved: 12/21/2014
Last Post: 11/02/2014
DIY bp gurus: will I need to corn my black powder for use in cartridges?
I was wondering what the effect would be if I did not corn my homemade bp that is to be used in .45-70 cartridges. I will be using dextrin in the mix.
John Boy
02-20-2013
I was wondering what the effect would be if I did not corn my homemade bp.
I don't have a clue - try it and see if the SD's over the chronograph are erratic or not. Presume your not also going to polish the polish the powder.
Texantothecore
02-20-2013
Polish the powder? I have not heard of that before. The only polisher I have is an old Sunbeam floor polisher and I don't think would work on a kernel of powder. Potentially very messy. Lol!
Nobade
02-20-2013
When I tried that it shot accurately enough but wasn't very powerful. IIRC I could only fit about 45 grains of powder in the case. After I started pressing it, a full 70 grains fits and it's way more powerful.
What was funny was the 44spl revolver and screened powder. 400 fps was all it could muster, easy shooting but really slow! BTW, the pressed powder does 850 fps.
John Boy
02-20-2013
Potentially very messy. Lol!
Not at all messy. Mix the powder with 6% water and tumbler dry down to 1.5 to 2% over a 24 hr period. Polishing froms a glaze and compacts the insides of the grains and is a standard step in the making of 'sporting gunpowder'. Without the process, ones just ends up with muzzle gunpowder with a low density.
So if you are not concerned with the SD spread of your powder and haven't really read up on on the standard processes making gunpowder - do what you want to do and see how it shoots. Good Luck!
Boz330
02-21-2013
What Nobade said. I add a little graphite to the corned powder so it will go through a powder measure smoother.
In a 40-65, screened powder gives me 1000+FPS for a 400gr boolit. With the corned powder I get 1200+FPS for the same boolit. Swiss gives me 1275FPS.
Nobade is getting his powder much denser than I am and the power comes from the weight. I did a test in a ML using screened, corned, and Kik, measured by weight and the velocities were within 50FPS of each other with the home made giving the higher velocities. But the volumes were considerably higher as were the ESs. But to answer your question you will need to corn it to get the density for a cartridge.
Texantothecore
02-21-2013
Quote Originally Posted by John Boy
Not at all messy. Mix the powder with 6% water and tumbler dry down to 1.5
to 2% over a 24 hr period. Polishing froms a glaze and compacts the insides of
the grains and is a standard step in the making of 'sporting
gunpowder.'
What kind of tumbler are you using to dry down your powder?
Are you simply putting in the screened powder into the tumbler or are you drying it down into a puck and shattering the puck to get the correct size kernels and then tumbling?
I do not have an area in which to use a tumbler, just my office at home so my equipment is kept simple and easy to store in a chest.
I am sort of thinking that I will have a brass or bronze cartridge collar machined that will hold an extra 25 or thirty grains of BP and then using a dowel or possibly one of the dies that are designed to compress BP to get more screened powder into the cartridge with one compression stroke as I have read on this forum that compressing smaller incremental amounts doesn't work very well. High SDs.
Boz330
02-21-2013
ESs are extreme spreads. I had no luck at all with incremental compression.
cal50
02-22-2013
Dextrin is a binder used in pyrotechnic black powder / star comps. It adds nothing positive for rifle propellant and will slow down the burn rate. You really want / need to press your powder in a die to obtain a good density before corning. Polishing the powder is simply tumbling the loose grained powder. You can add graphite and it will give it a nice color and makes the powder flow nice.
Compressing your powder in a press die gives it the density for good BP. Corning it only produces the various grain sizes.
cal50
02-22-2013
Here is a good read on the topic: http://www.gunthorp.com/Mfg%20Black%20Pdr.htm
Texantothecore
02-22-2013
I just read that link and it is very good, the best I have ever seen. The simplicity of the equipment is quite impressive, to say the least. I will be probably be building a press in the very near future. Thanks.
Do you approximately how much pressure would be required to press a one pound batch to 1.7 Grams per CC? From the description it doesn't sound as if it is much.
For those of you following along and thinking about making your own, the link is a must read.
cal50
02-22-2013
Quote Originally Posted by Texantothecore
Do you approximately how much pressure would be required to press a one
pound batch to 1.7 Grams per CC?
You would not press 1lb at a time. I press about a cup or more at a time into my die. I have a harbor freight press and I put a pressure gage on the hydraulic jack. I press the powder and keep adding pressure until it holds steady on my gage for 20 minutes. Once the pressed powder comes out of the die it sounds like china if tapped. I use a 3" diameter die and the powder "puck" is around 5/8" thick. I wait until dry to corn it.
cal50
02-22-2013
I did the math for my ram size & die so my pressure will vary from other set ups.
If you have a graduated cylinder just put 10 or 20 CC'c of powder in the cylinder then weigh it to get an idea of density or grams / cc.
I can say my powder performs better than Goex but that has a lot to do with milling, sulfur content, quality of charcoal and my process.
Texantothecore
02-22-2013
I would think that the Harbor Freight 1/2 ton arbor press would do just fine in this application. I will look at one tonight.
cal50
02-22-2013
You really want a press that holds pressure. A screw type or hydraulic with a gage is even better. You will be amazed at how much powder compresses down and it takes several more pumps on the jack to get it to settle down.
Texantothecore
02-23-2013
Quote Originally Posted by cal50
You really want a press that holds pressure. A screw type or hydraulic with
a gage is even better.
I had thought that a screw press might work pretty well and i will price the parts this weekend.
The other idea that immediately came to minid was making use of a 2 ton shop jack which will hold up an F150 pretty reliably. I am sort of spinning one around in my mind, upside down, sideways and right side up.
Boz330
02-23-2013
My screw type press. Not sophisticated but works for what I'm doing. After a very short time you can tighten it more.
Texantothecore
02-23-2013
That vise occurred to me too. I'll bet that works like a charm. I may look for one at one of our shops that specialises in (mostly worn out) tools and I'll bet I can find one that is suitable. Thank you for that pic as it is really valuable to see the simplicity with which you have accomplished the task at hand.
John Boy
02-23-2013
What kind of tumbler are you using to dry down your powder?
For starters, I haven't made 'fire cracker' powder since the age of 10 or 11. What I posted to you is what the major black powder manufacturers do and if not done - the results. Would stand to reason - if one runs with the big boys - ones powder can't be all that bad... but not equal to!
cal50
02-23-2013
The vice is a better choice than and arbor press with no way to hold pressure.
BP has been around for a LONG time and its no secret how to make good powder. With common sense and reasonable safety measures you can mill your own powder.
As I mentioned before charcoal is the key to good powder. You want soft wool charcoals for a fast burn rate. Willow, grape vine , balsa are all excellent charcoals. Sulfur content also affects burn rate, I use 10% sulfur.
John Boy
02-23-2013
You want soft wool charcoals for a fast burn rate. Willow, grape vine , balsa are all excellent charcoals.
...and preferred, one wants the branches of alder buckthorn**, not ground up trunks, cut and harvested in late winter just after the ground has thawed and the sap begins to rise in the trees. Next, remove the bark. Then the branches should be ricked for 3 years to dry. Then build a closed retort and char the branches at no more than 300 to 320 degrees Centigrade for 8 hours which gives a fixed carbon content of about 65% in the finished charcoal and doesn't flash off the creosote for sporting powder.
Grind to a particle size range of 2 to 10 microns and then mix with the salt petre and sulfur.
One has to remember, the sap (glucose) in certain woods is the Ignition Engine of original gun powder
** Contact one's forestry department and they will tell you where to find alder buckthron in your State. There are acres of it in certain States. I pulled 2 dozen root shoots and sent them to a BPCR shooter who is growing a hedge row of the alder for charcoal to make his own powder. DO NOT USE YELLOW MAPLE!
Texantothecore
02-25-2013
I am not sure which of the preferred woods grow in Texas. We do have a grape industry so that might generate some good charcoal for me, but I suspect the Buckthorn is about 800 miles north of me. The ground actually freezes? Hahaha
Texantothecore
02-27-2013
How much pressure are you running? I am trying to figure out what house jack to use as well as whether the frame should be sistered 2x10s or steel. The use of resin in the production of the pressure plungers at Gunthorp leads me to believe that the pressure may not be that much.
I most likely will be using a cup of BP at a time as that seems to be a rational approach.
Texantothecore
02-27-2013
For those of you who are following this thread and who live in the South:
Most of the suitable woods mentioned by others are are far north of us.The Confederacy used Cottonwood for the charcoal and it seemed to work well.
I suspect that just picking up dead Cottonwood branches would work perfectly because they lose a lot during the year as it is a very soft wood and won't take much wind. I should probably go out after the next hurricane and get a lifetime supply.
felix
02-27-2013
Cottonwood was the choice box material during WWII for parachuting ammo out of planes. The boxes blew apart when hitting the ground leaving the ammo easy to pick up and run with. A major saw mill is still operating in New Madrid MO just for making these boxes with. Lumber not contracted for by the military is used locally for building "share cropper" houses and other very cheap uses. Stacks of lumber are all over the town where the mill is to let the lumber dry. It's the most warped lumber in the world when dry; it looks like it anyway. Want a splinter? Play cowboys and indians in the stacks.
If some folks want sawdust, I probably can get enough for anyone who requests some. Cannot be in a hurry, though. All I would ask in return is the fees paid for mill (if any) and PO. I will get fresh only because I must see the logs being processed before I make requests. They mill anything that floats down the river (via lumber jacks) for various uses.
John Boy
02-27-2013
...but I suspect the Buckthron is about 800 miles north of me.
Texan, you have willow trees in TX? Alder is in the same family.
Texantothecore
02-28-2013
I am sure that we have something in that family but I have not seen anything that resembles a willow or alder. There may not be enough water to support the plants. Since Cottonwood was used to produce military grade black powder I am sure that it will produce terrific powder. And as as a bonus I can pick branches up on the way to work, at lunch and on the way home after work. They are everywhere down here.
Texantothecore
02-28-2013
Ouch. We used to get splinters from railroad ties that made up our redoubt.
cal50
02-28-2013
Quote Originally Posted by Texantothecore
How much pressure are you running?
I will take a look at my pressure gage I mounted on the hydraulic jack. I know that I ran it to the gages max PSI reading because I do not have a pressure cut off for the gage and did not want to break it.
Boz330
02-28-2013
Quote Originally Posted by Texantothecore
Since Cottonwood was used to produce military grade black powder I am
sure that it will produce terrific powder. And as as a bonus I can pick
branches up on the way to work, at lunch and on the way home after work. They
are everywhere down here.
Unless you are making a tremendous amount of powder you can get enough to keep you busy for awhile in just a couple minutes. A one gallon paint can retort packed as full as you can get it will last you quite awhile. If you use the Harbor Freight ball mill your batches will be between 4 and 6 ounces and the bulk of the that weight is the KNO3. You do have to strip the bark off of the wood.
Texantothecore
02-28-2013
Thanks for the estimate. I had it in the back of my mind that 100 pounds of branches would yield about 4 oz. of charcoal but it appears that my estimate was off a bit.
So I'll have to back off the search for an old oil drum. And a remote spot for a big bonfire. LOL
Texantothecore
02-28-2013
I am not sure I could successfully rick Cottonwood for three years as the termites down here would find it and dine on it. They can smell wood at 5 miles.
When I worked in the wood industry it was generally considered sufficient to rick a one inch sawn board for ten days. Probably less down here in the South as the combination of 100 degree heat and a twenty or thirty mile per wind will dry things down to the point of being fire hazards in about two or three days. When that type of weather pops up all the ranchers and farmers start looking for rain to keep the fires at bay. Texas is really dry.
I will probably split the Cottonwood down to 1/4" or 1/2" sections and throw them on a very cool BBQ to dry them out. The fire will also keep the termites out. LOL
Boz330
02-28-2013
A typical batch is 150grams KNO3, 30 grams charcoal, 20 grams sulfur. That is 3.2 ounces. 30gm of charcoal is more bulk than the 150gm of KNO3. It is very fluffy. I normally do several batches and then wet it and press it so I have a couple pounds when finished. It is a slow process but there is the self satisfaction of doing something yourself.
Faret
02-28-2013
Quote Originally Posted by Texantothecore
Thanks for the estimate. I had it in the back of my mind that 100 pounds of
branches would yield about 4 oz. of charcoal but it appears that my estimate
was off a bit.
So I'll have to back off the search for an old oil drum. And a remote spot for a big bonfire.LOL
I used a metal 5 gallon bucket and a turkey fryer turned just about all the way up worked good too!
Boz330
02-28-2013
I did my first batch in my Brinkman smoker. It worked. The last batch which was Tree of Heaven I did in the fire at deer camp, appropriate I thought since that is mainly what I use my powder for.
Nobade
02-28-2013
I have been using an old propane fired BBQ grill. The 1 gallon can fits under the lid so it holds the heat in and works very well. I just turn it up all the way and it doesn't take TOO long.
ofitg
02-28-2013
Good technical info for making charcoal at this site -
http://www.musketeer.ch/blackpowder/charcoal.html
The finished charcoal will weigh roughly 20% as much as the wood you started off with.
The key is to get the wood temperature up to 350 C (660 F) and hold it there long enough for the conversion to take place. How hot does it get inside an electric lead-melting pot?
ofitg
03-01-2013
A couple years back I was using a small LEE pot. I set a steel disc "lid" on top to hold the heat in. It took about 45 minutes from start to finish, yielded roughly 3/4 ounce of charcoal per run.
cal50
03-01-2013
Quote Originally Posted by Texantothecore
How much pressure are you running?
My press is the Harbor freight 12 ton shop press and its useful for a LOT of projects and repairs:
http://www.harborfreight.com/12-ton-shop-press-33497.html
I installed a liquid filled pressure Gage that has a max reading of 5000 PSI. With the hydraulic jack pumped up to 5000 PSI on the gage that imparts a ram pressure of 10370 force or a little over 5 tons force ( 1 5/8" diameter cylinder in the jack). I compressed my powder at this force in my 3" PVC press die and continue to add pressure until there is no more compression loss and let it hold there for 30 minutes. Basically I am adding a cup of powder in my die seperated by a metal disc, another cup of powder then another disc, etc until I have around 4" total height of "pucks" pressed in my die. After the hold time I release the pressure, remove the clamps from the die and separate the powder pucks and let dry.
Texantothecore
03-02-2013
Wow! That is a really nice set up. Capable of running some real volume on the odd Saturday.
I have two Bible study friends who shot my rifle during a guys Bible Study weekend and they are really interested in .45-70 black powder now. I think both of them would love to build a set up like this in one of their garages for our use.
Where did you get the hydraulic gauge? I am having a problem finding one that is for a reasonable price.
Any tricks of the trade to using the press?
And thanks for the info on the 30 minute dwell time. That is very helpful.
Texantothecore
03-02-2013
Some dollar issues:
For those of you following along, the Harbor Freight 12 ton press is $129.00. Cheap. The shipping is somewhat expensive because of the weight but I don't know if this will apply to presses bought in the local store or not.
The 3" pvc pipe will run you about $15.00 at Lowes and you will only use a 5" section.
Update: The 12 ton jack is $129.00 if purchased at the store. This is looking like a go.
Texantothecore
03-02-2013
Interesting research on Cottonwood:
It appears that Cottonwood's density and weight per cubic foot is identical to willow and alder. Could be some great powder coming out of this shop.
ofitg
03-02-2013
Cal50, assuming you use Schedule 80 PVC pipe, your pucks are 2.9" diameter? If I'm doing the math correctly, the puck would have a frontal area of 6.6 sq.in.
According to one of my books (Chemistry of Powder & Explosives. by Tenney Davis) the big manufacturers compress their BP with pressure in the neighborhood of 1200 PSI.
Nobade
03-02-2013
Quote Originally Posted by Texantothecore
It appears that Cottonwood's density and weight per cubic foot is identical
to willow and alder. Could be some great powder coming out of this
shop.
I have some cottonwood but haven't made charcoal out of it yet. But according to Fly over on the muzzleloading room, it makes a very fast powder that fouls terribly in guns. It works great in fireworks where you don't care about fouling, but isn't too great for rifles.
cal50
03-03-2013
I had the gauge that came off of something else. Larger gauges did not have the fine line increments and the gauge I used was free. I did drill & tap a hole in my jack to attach it. Some hydraulic jacks have a service port which you should be able to plumb one in easy.
cal50
03-03-2013
Quote Originally Posted by ofitg
Cal50, assuming you use Schedule 80 PVC pipe, your pucks are 2.9" diameter?
If I'm doing the math correctly, the puck would have a frontal area of 6.6
sq.in.
According to one of my books (Chemistry of Powder & Explosives. by Tenney Davis) the big manufacturers compress their BP with pressure in the neighborhood of 1200 PSI.
1.7g/cc is the target density of the powder you are pressing.
For my die and the column of powder I was pressing I am getting excellent density. Its been a LONG time ago but I actually did the math.
Here is a good read-
http://www.creagan.net/fireworks/blackpowder2.html
Info on presses and jacks with gages-
http://www.skylighter.com/fireworks/how-to-make/hydraulic-rocket-press.asp
Cut / paste
1) Basically you can make the pucks (cylindrical pressed "cakes" of powder)
every size and thickness you want, but:
- making very small diameter pucks it will take time to convert a whole batch into pucks, given the fact that one pressing can take from 15min to half an hour, due to the necessary dwell time.
- Larger pucks require higher pressing loads to be adaquately compressed, due to the higher friction.
- Thick pucks will take longer to dry.
- I press 12cm diameter pucks 1cm thick, weight is about 120 grams each. I would not exceed the 15mm thickness.
Texantothecore
03-03-2013
Thanks Cal50 that is just the type of info that I am looking for.
New question: Assuming my goal is FFg, how much yield would I get from the shattering of a puck and sifting through a screen?
Would there by any value to pushing larger pieces through the screen and resizing them to FFg? Or would I just end up with more dust.
Would dextrin increase the immediate yield of FFg and cut down on the dust?
Texantothecore
03-03-2013
Are the plates that you use between the charges of powder 1/2 inch?
That would give a 4 inch column.
How big is the base plate you use to support the powder die?
ofitg
03-03-2013
Quote Originally Posted by cal50
1.7g/cc is the target density of the powder you are pressing.
Cal50, applying 10370 pounds of force to 6.6 sq.in. of powder (inside a 3" PVC die) works out to 1570 psi... it is clear that your system is capable of duplicating factory results.
Texantothecore
03-03-2013
I found a 0-10,000 pound liquid filled gauge at McMaster-Carr for $42.00 and it would seem to me a very good buy for the press.
Scratch that. Mcmaster-Carr has a liquid filled gauge, 0-15,000, for 25.00. It is for use with hydraulic oil. That is the one I was looking for.
cal50
03-03-2013
Quote Originally Posted by Texantothecore
New question: Assuming my goal is FFa, how much yield would I get from the
shattering of a puck and sifting through a screen?
The corning process really produces all grain sizes and is hard to control for specific grain size. Some break the pressed powder with a wood bat or mallet then run through your screen or sieve. I used a roller set up like a flour or grain mill and adjusted the roller spacing to tweak grain size. If you have large grains like cannon or F you can re-run but you still get "corning dust" which is 5F and great flash pan dust.
Pressed powder needs no binder as Dextrin. It will only slow the burn rate and not help grain size IMHO.
cal50
03-03-2013
Quote Originally Posted by Texantothecore
Are the plates that you use between the charges of powder 1/2 inch?
Mine are thin like the plastic separators used in a hamburger press. You can use tinfoil but I like thin plastic. The pressed powder pucks separate easily with some divider used. I put one in the press die before I add any powder, add a cup, add divider, add a cup of powder, repeat till I reach the top of the die.
Then I press the entire column.
cal50
03-04-2013
Quote Originally Posted by ofitg
Cal50, applying 10370 pounds of force to 6.6 sq.in. of powder (inside a 3"
PVC die) works out to 1570 psi... it is clear that your system is capable of
duplicating factory results.
I know I am a little higher on compression PSI but I am close and a little more on the dense side (LOL!).
I did a comparison with Goex in the same granulation in a volumetric cylinder and weighed the same volume and I am damn close.
For performance testing I used a 3" PVC pipe section filled with dirt and two caps welded on. I fired it from a mortar straight up and recorded the flight time for a weighted dummy shell. My powder was noticeable faster / hotter and added a full 4.8 seconds to the total flight time from ignition to the shell impacting the ground.
Texantothecore
03-04-2013
Quote Originally Posted by cal50
I press 12cm diameter pucks 1cm thick, weight is about 120 grams
each.
CAl50: Just checking numbers here.
You stated 12 centimeter pucks which would be 4.7 inches in diameter. Are you using a 5 inch PVC pressing die?
LIMPINGJ
03-04-2013
Has anyone used Birch to make powder with? Looking at the fireworks links it seem to be fast but how dirty compared to Willow is it? I have both woods on my place and was just wondering about how Birtch would work?
cal50
03-04-2013
Quote Originally Posted by Texantothecore
Are you using a 5 inch PVC pressing die?
My press die is 3"PVC.
Texantothecore
03-04-2013
Quote Originally Posted by cal50
My press die is 3"PVC.
Thanks. I just wanted to reconcile the numbers.
I am also looking at the twenty ton press which is another 70 bucks and it may be that I could go with a larger diameter puck. Or not.
Texantothecore
03-04-2013
Quote Originally Posted by ofitg
Ofitg, can you do the math for a 6 ton press? Would it be adequate for
generating say 1570 PSI?
Scratch that 6 ton press. It appears that it has only has two inches of travel and I would think that you would have to go through several pressings, inserting spacers after each compression. Let's keep it simple.
Texantothecore
03-04-2013
The first plate that you use to press down on the powder... is that just 1/4" steel plate? The one that is immediately below the ram?
cal50
03-04-2013
My block between the hydraulic press & the powder is just a round block of Delrin material. A bar end actually. You can use about anything that can survive the press pressure. I try to stick with alloy or plastic (non sparking) but for the press I doubt it makes any difference.
Texantothecore
03-04-2013
Thanks for the info on the delrin round. That is really helpful.
There have been some real surprises in our discussion and that has been another.
Texantothecore
03-05-2013
Quote Originally Posted by cal50
My block between the hydraulic press & the powder is just a round block of
Delrin material. A bar end actually. You can use about anything that can
survive the press pressure. I try to stick with alloy or plastic (non
sparking) but for the press I doubt it makes any difference.
I will probably go with a 1/4" steel plate that will hold 36,000 PSI and I think it will work well. We in the South don't have much of a problem with static charges: I haven't seen one since I moved here 15 years ago. When I was young I lived in Wisconsin and the static charges with which I used to torture my sisters in the winter were like bolts of lightning.
Texantothecore
03-05-2013
Sources for some of the stuff Cal50 is talking about:
Mcmaster-Carr
1. 0-10,000 PSI pressure gauge, liquid filled, pipe connection Brass NPT Male, 2 1/2 inch dial,numeric increments every 2,000 psi, +-1% accuracy in the gauge's midrange.
part number: 4053K15 $25.14 (bottom connection, others are available)
Mcmaster-Carr stresses that pressure gauges should be purchased which have a range that is 2x the range you will be working at as the cheaper gauges are accurate in the mid range, not so much in the low and high ends of the range. A more expensive gauge will be accurate througout the range but we aren't looking for that type of accuracy or price.
2. Delrin short rods, three inches in diameter, 1/2" thick(long), for the surface directly underneath the ram.
Part number: 8582K11 $5.47
Look at the listing of short rods in 3" diameter. They can be purchased to 6 inches long at a very reasonable price and can be sawn to size with a hacksaw. Might be some useful stuff in those rods.
After further reflection I am going to go with a Delrin short rod that is 1" long by 3" in diameter as I feel that it will be much stiffer and will transfer the pressure much more effectively.
Part Number 8582K21. $9.56
Texantothecore
03-05-2013
You stated earler that you released the clamps on the powder die and I was wondering how you clamp the die. Is this step critical?
cal50
03-06-2013
Quote Originally Posted by Texantothecore
You stated earler that you released the clamps on the powder die and I was
wondering how you clamp the die. Is this step critical?
Not at all and I will dig it out and take some pics.
My 3" PVC is slotted completely down the side on my table saw. Hose clamps are placed around the outside and the clamp screws staggered for complete coverage/support for the pressed powder column.
It's only needed to tighten the clamps to support the area you are applying pressure to.
Once you are done pressing you loosen the clamps and slide your press cake out of the die. Some corn it now, others let it dry then corn it.
It might not appear flammable in this moist and pressed state but I assure you that it is.
Texantothecore
03-06-2013
I had never thought of corning it with 6% moisture in it but it seems to me that it might cut down on micro dust in the air which is the real safety issue with Black Powder. Many of you are not old enough to remember but when I was a kid charcoal factories blew up from the microdust in the air and even more common were explosions at wood working operations, grain mills, etc. OSHA came in and required some rather sophisticated dust recovery systems and those problems have disappeared.
I am suprised at your slit powder die and would never have guessed that particular technique would be used but it makes a lot of sense as removing the stacked pucks with a relaxed die would be substantially easier and less damaging to the pucks.
Pictures would really help us visualize your set up and its sophistication. Thanks.
Texantothecore
03-08-2013
Can you describe the roller set up you have and how it works? I am curious about the distance between rollers and how it relates to grain size and it seems to me to be the best way to turn the puck into useful powder. Once you find out the initial settings it should stay about the same although I can see where it might change with large changes in ambient temperature.
Texantothecore
03-08-2013
Quote Originally Posted by ofitg
Cal50, applying 10370 pounds of force to 6.6 sq.in. of powder (inside a 3" PVC
die) works out to 1570 psi... it is clear that your system is capable of
duplicating factory results.
Ofitg, can you provide the formulae that you used for your calculations? I am particulary interested in the formulae that allow me to calculate the pressure in the cylinder of the press ad convert it to presure at the ram head as I intend to drill and tap the cylinder to install the pressure gauge so that I can repeat the pressure. I have tried to backwards engineer your calcs but I am missing something.
Update:
I found the calculation to use and was able to duplicate yours and Cal50's results perfectly. thanks for your help to both of you.
cal50
03-08-2013
Some pics of my press die. This is a larger diameter one than the 3" I referenced earlier. I did some experimenting a while back and this is the one I have used the most and currently. Its PVC plastic pipe with a table saw cut down the side its entire length. I slip on standard hose clamps and tighten them down before use. I have a turned solid aluminum slug for my press block. Also pictured are aluminum spacers I cut from flat aluminum to place between my pressed powder pucks.
Basically I tighten the clamps and set my press die on a sold piece of aluminum for the base. I add moist powder into the die , spread it around to level it out , drop a aluminum spacer on top , add more powder , level it a bit, drop a spacer , repeat, repeat.
Once to the to of the clamp area I put it under the hydraulic press and crank up the pressure. I place a rag or paper towels around the bottom because the water you added will be seeping out the bottom and the rag catches it. I check every few minutes and add pressure until it holds constant on my gage then let it sit for around 20~30 minutes.
Once its "time" I release the press pressure , use my power screwdriver and release the hose clamp pressure and slide the aluminum press block and the pressed powder from the die. I separate the powder "pucks" and then weigh them on a scale and with a marker write the weight on the powder puck. I can monitor the drying process and can tell when its dry when the weight stabilizes. I have and old cooler filled with silica gel and I can put them inside to completely dry them if needed. My relative humidity in Ohio is around 40% in the basement so totally dry is lighter than weighing it in 40% relative humidity.
Once dry you can corn it by your favorite method.
Stagger the hose clamps to support the powder around the press area-
Aluminum spacers for in between powder in the die~
Aluminum press slug~
Press Die~
cal50
03-08-2013
Powder / ball mill~
You want or need a decent ball mill to make good BP. I purchased a tumbler drum from an online shop and made my drive for it. I had several DC servo motors and speed controls so I made a frame with belt and drive wheels from a dead belt sander. I can adjust the speed and have it set around 50~60 RPM. Inside I have about 1/4 the volume with brass and bronze lapping balls and pieces. This is the part that does the powder milling and grinding. I do my milling in 3 steps. 1st load the KNO3 or potassium nitrate goes in and runs for 2 hours. I stop it and add the sulfur and run it for 2 hours. Last stop I add the charcoal that has already been milled and let it run for an hour.
Nobade
03-09-2013
That's a good tip, I hadn't thought about a DC drive. Makes it easier than changing gearing. Keep an eye open for old treadmills that people are giving away or selling at yard sales. They have variable speed DC drives in them. They also work for refitting small lathes.
Texantothecore
03-09-2013
Is that a 6" diameter die? It seems huge.
Texantothecore
03-09-2013
Cheap screening for corning:
Mcmaster-Carr (www.mcmaster.com)
Lightweight-Particle-Filtering Stainless Steel Wire Cloth, Size 12x12 inches in the most commonly used mesh sizes:
mesh size P/N
10 x 10 9238T52 $8.62
12 x 12 9238T24 $5.77
14 x 14 9238T53 $7.38
16 x 16 9238T25 $5.77
20 x 20 9238T29 $6.30
24 x 24 9238T42 $6.67
30 x 30 9238T44 $5.77
50 x 50 9238T45 $4.93
McMaster has no minimum order.
I have read a great deal about corning and the number of different size ranges quoted is amazing. I will say that Swiss grain size is smaller than Goex and that may explain the speed of the Swiss powder.
Texantothecore
03-09-2013
The wide angle lens fooled me. The pictures are great! What a set up.
Do you have a picture or 2 of your roller set up for crushing the pucks. And can you explain just how is it used in practice?
cal50
03-09-2013
No pics handy as the corning machine is at my friends house. He was using it last (he makes good powder also).
The roller corning set up works well if your pressed pucks / powder discs are similar in size ( thickness) to run thru the rollers. This is where we experimented with pressed powder thickness of smaller diameter / fatter Vs larger diameter puck and thinner pressed powder. The thinner pressed powder was definitely faster and easier to corn over a thicker piece running it thru rollers.
Our corning mill looks similar to what is pictured below but with a hopper and crank attached-
http://www.homebrew-supplies.ca/viartshop/product_details.php?category_id=118&item_id=369
We made the rollers from knurled aluminum and are adjustable for width / thickness.
Texantothecore
03-11-2013
Thanks for the link as it is very instructive. I would not have thought of three rollers but that looks like a good solution to the problem at hand. The first two rollers crush the puck and the third crushes it to the wanted size. Thanks for the info, it will be used in my shop.
Texantothecore
03-11-2013
I was running the whole system in my head and the question of puck thickness did come up as it seems to me it might increase yield on the first pass if one used a thinner puck. Have you had any experience with this? As you have written, the separators for the pucks could be simply aluminum foil and a full lb done on each pressing as you do now but you might use 1/2 cup per puck in order to produce a thinner puck that broke more consistently.
Would this be something I need to check out?
Being a manufacturing guy, the question has also come up about a 6 ton press. Because of the short working distance of the ram (2 inches), the procedure would resemble the following:
Load two pucks
Using a press plug designed for this purpose (extra long) Press to 100 or so lbs. This could be a very low pressure perhaps 25 lbs as all we would be doing is decreasing the volume of loose powder to a level at which I could get four pucks into a 4 inch long die.
Load the second two pucks and a press plug for the final press. It would seem to me that if we are going to compress to 1600 psi in the final compression the initial press action should be of little importance in the formation of the final product. This would allow me to load press 1 and while it was working its magic, load press 2. Essentially produce 4 pounds in a very short time and since we are going to have about 4 people in the project it would allow all of them to produce a fair amount of powder in a relatively small time span. Twice the production of a 12 ton press without any decrease in quality.
Boz330
03-11-2013
Here is my setup but I'm not doing near the quantity that you guys are doing. This is a ceramic coffee grinder. The knurled mill set up is really nice looking and I bet a lot quicker than my setup.
Texantothecore
03-11-2013
What grinder is that? I am looking at a Corona grain mill that is extremely popular in South America and it will, in two or three passes, produce fine flour from grain. It is also sturdy enough to be cleaned with a hose between batches of different materials.
Texantothecore
03-11-2013
I am hoping to use up about 4 lbs per month and doing it in one hour would be very nice. Actually that would be less time than it takes to drive to the gunshop and buy it for 25.00 per lb.
I spend a lot of my shooting time at the range with people who are fascinated by black powder and I always hand them the rifle to shoot to give them a real feel for the sport. After the trigger pull they, like me, stand up and cheer for God, Country and Texas.
But it is getting expensive and I would like to be able to continue to do this.
I originally started shooting ML as a direct result of Civil War re-enactors who had a set up at the St. Louis County Fair one year. They handed you a rifle with a small charge 5-6 grns in aluminum foil and you loaded it as a blank and fired it. I fell in love with BP right there. I want to "Pay It Forward"and do the same for others. I love doing that.
cal50
03-11-2013
That's something to consider and your process can be tailored to your setup or demands. I like my pressed powder to come out of the die about 3/8" to 1/2" thick. The thickness can be adjusted by the amount of powder put in the press die and pressure / time compressed. Mine was run thru the rollers to corn but as I made a reference to the thickness of the pucks need to be a certain range to feed through the rollers without making a lot of dust or wasted grains. I am always looking for a better and simpler way and the roller works but mashing it with a wood bat and sifting does as well.
cal50
03-11-2013
I hope you wear gloves and safety glasses when cranking... Even that small amount of powder will bark at you if ignited.
Texantothecore
03-11-2013
I learned a long time ago that welding gloves work. Period.
And lately I have learned that goggles are not enough for pouring bullets, you need a full face mask. The lesson learned was very cheap but unforgettable. A tiny (probably 1/2 the size of a pinhead) piece of molten lead popped up and landed on my nose and hurt like the dickens but did not leave a permanent scar. I shut down and drove directly to Lowes and bought a full face safety mask for 13.00 and I haven't that problem again. I am noticeably more careful too and as a result there are no scars on the facemask from lead that has gone into the air.
Texantothecore
03-11-2013
I will probably start with the old baseball bat technique and graduate to a more hi tech solution if needed. And I will probably experiment with such things as puck thickness, development of a standard puck size using a weighed charge and increasing yield on the first pass.
Boz330
03-11-2013
Quote Originally Posted by Texantothecore
What grinder is that?
I couldn't find a name on it. It is a ceramic grinder to avoid sparks and IIRC I got it from Amazon. You really don't need for it grind that fine. My problem is I get way more fines than I can use in a flinch lock. I found that 3F gives me the best groups and ES of any other granulation.
@ cal50 safety glasses are a permanent fixture on my face since I was 3 and leather gloves. I wish that I still had a connection to get the nomex flight gloves that I use to be able to get.
cal50
03-11-2013
The corning process is the most hazardous IMHO. Pressing or breaking pressed powder is less risky than running thru any grinder or friction /abrasive contact points. Ball mill explosions are rare by comparison to corning phase fires.
Always try to corn powder when the relative humidity is high. Very dry conditions usually are better for generating static electricity. I ground my ball mill and corning roller when in use. I have tried to ignite atomized powder by static electricity with no success.
That does not mean it can't happen though.
Long sleeves, gloves, glasses a face shield and small volumes of powder = safe operation.
Texantothecore
03-11-2013
I will be using an emptied windex spray bottle to increase the relative humidity in the area in which we are working. I haven't seen any static electricity in the area as Houston is very humid, but you never know.
Cal50, how do you ground your machinery?
cal50
03-11-2013
Simple copper wire from the mill to a ground rod or a cold water / copper pipe. Perhaps overkill but simple to do. At a minimum discharge yourself by touching a grounded object similar to working on electronics.
Boz330
03-12-2013
The real danger would be the fine dust from the grinding process with static electricity. There are lots of videos trying to set off granulated powder with static electricity with no joy. OTOH how many grain silos have blown up and that dust isn't near as flammable as BP.
Texantothecore
03-12-2013
Many, many years ago in what increasingly seems to have been a different galaxy (LOL) I worked in the wood industry. We had automated routers going 24/7 and dust was a real hazard although we never had an explosion. It's the microdust that will get you. The lack of explosions in these envrionments these days is a good indication of how well the companies use their dust control systems.
I wish we had a dust control expert on the board to lend us some insight. I do know that the operations for our group that might generate dust will be done outside in the wind. It is going to be a chapter (ha!) in my operations manual for the group and will play a big role in the initial teaching phase for the guys. Fortunately most of the guys in the group are tech heads (mostly engineers) from the oil industry and they are really adept at picking up technical data and have, like me, worked in hazardous environments. So they are familiar with the problem.
Texantothecore
03-13-2013
I think we are going to go for the 6 ton press to start. It should be quite fast and once we get the preliminary press work done, that is to reduce the volume of the powder, it should go just as fast as the 12 ton press. As we add people we can add the smaller presses for very little money.
We can also use the savings on the press to look at a better grinder like the Corona as I think and have read that the initial grind is pretty key and it will speed things along. We will also probably get a Chrony (you shoot it, you buy it!) to do some really good testing of our results. Nothing spectacular, although the tech heads I hang out with will probably want the Biggest- Baddest-Super-Duper-Ultra-Turbo-Extreme-Wireless Chrony in the world, but I can handle them. Data is data.
Texantothecore
03-13-2013
For the 1700 members and guests who are following this thread, some observations:
1. Black powder is wonderfully useful, more so in many ways than modern powder. Small charges work well as well as full bore Zombie loads if you take the time to read the many threads on how to do this safely. This allows one to use only the amount of powder and projectile that is needed to get the job done, a great way to preserve powder and lead in this time of, quite frankly, stupid prices and shortages.
2. Given a small set of ag chemicals from Home Depot, you can make:
a. A lower speed powder that is suitable for short range plinking, rabbits and squirrels, birds etc. Call it the Trail Boss of black powder. It is black powder that is screened and dried but not corned. In a .45-70 it will allow you to get a rabbit without the problem of vaporizing it with a full full bore load. It is also quickly made on the kitchen table... if you are single or want to be. LOL
b. A much more powerful corned powder that will, with sufficient caliber, splash most anything on the North American continent. Which is what we are discussing here.
Wonderful stuff.
Texantothecore
03-13-2013
I recently saw a reference to a French grind method that is designed to be safe but is used to disable clumping during the initial grinding process for Potassium Nitrate and Sulfur. The French pour 1/3 of the charcoal into the Potassium Nitrate drum and the remainder in the Sulfur drum. Apparently the amount of charcoal in the Potassium Nitrate drum is below the level at which it becomes explosive and the same appears to be true for the sulfur mix of sulfur and charcoal.
With a two drum tumbler from Harbor Freight you could use one grind sequence rather than three grind sequences for your initial reduction of the black powder components which would really speed things up and as a bonus it would decrease the handling of the components and thereby render the process a bit safer. The French claim that it is very safe and I haven't heard anything to the contrary.
Texantothecore
03-13-2013
I think that most of the silo and factory blowups you read about are due to sparking from 220 volt, 3 phase motors, not static electricity. Most grain elevators or silos have motors and blowers in the bottom that are used to circulate air through the grain to keep it from deteriorating and catching fire like the proverbial oily rag.
My father used to design these motors and the modern versions are very high tech. Surprisingly so.
Texantothecore
03-15-2013
Goex uses, I have read, 12 to 24 screens whereas Swiss uses 16 to 30 for ffg and that may account for the better performance.
Texantothecore
03-19-2013
Some observations and questions:
The Confederacy produced superior black powder and the English were shocked at the high level of technology and the excellent powder that was the result of that technology. The innovation that was most striking was the heating of the potassium nitrate (KNO3) by injecting steam into the large pot holding the KNO3 until it became a slurry (water + KNO3)and then mixing it with sulfur and charcoal and then processing it normally.
We do much the same when we use the CIA process for mixing the components so I would think the use of that method would be entirely adequate particularly if the components were carefully ball milled before mixing.
ofitg
03-20-2013
We do much the same when we use the CIA process for mixing the components so I would think the use of that method would be entirely adequate particularly if the components were carefully ball milled before mixing.
In his book Black Powder Manufacturing, Testing & Optimizing, Von Maltitz describes a "precipitate" method used by the Chinese as far back as 600 A.D.
Instead of pouring the hot slurry into frigid alcohol (per the CIA method), the Chinese poured the hot slurry onto a cool marble slab.
cal50
03-20-2013
I have made some VERY energetic powder from willow charcoal. Balsa or grape vine charcoal is supposed to be top shelf for the coal aspect.
I have not seen any Balsa to cook charcoal from...
Texantothecore
03-20-2013
Quote Originally Posted by ofitg
Instead of pouring the hot slurry into frigid alcohol (per the CIA method),
the Chinese poured the hot slurry onto a cool marble slab.
That is interesting and it seems as if I will have to take a look at that book at some point. A fast cool down would really drop the KNO3 out quickly and thoroughly.
I haven't yet seen a full description of the Confederate manufacturing process as the text seems to be written by people who are overly thrilled with the steamed KNO3 and they never get to the rest of the process. It seems entirely possible that the rest of the process was very much as we use today.
Thanks for the citation and the info.
Texantothecore
03-20-2013
Quote Originally Posted by cal50
I have not seen any Balsa to cook charcoal from...
I played around with model airplanes and balsa in my youth and I have speculated that one pound of balsa might just fill the back end of my Kia Soul to the top. That stuff is really light. And expensive. I used to save up my allowance for balsa and then go on a buying binge (say $5.00) every two months or so. I haven't looked at the price for decades and it might be a bit cheaper than I remember.
The Cottonwood looks as if it will do quite well particularly if thoroughly milled and that is what I plan to go with for the moment.
One of the reasons I like the CIA method is that you can mix a pound at a time rather than the 4 to 6 oz. that you get out of a straight ball mill operation. You then do an initial screening through a $2.00 dollar Walmart flour sieve onto a piece of paper, let it dry and pack it into cans until you get the time to further process the powder. My time is quite limited by Real Estate work and this particular batch process seems to fit my lifestyle quite well.
I am going to try and store the green meal in one quart steel paint cans from Lowes ($2.97) until further processing. I expect to have 4 pounds of green meal as a max and will consider myself quite lucky to have the time to get that much done. It will probably be more like 2 pounds at any one time.
Do you see any problems with this approach for storage of the green meal?
It seems safe to me as the steel cans that are normally used commercially are about the same. At one point some of the hardware stores carried 1 quart cans which appeared to be identical to the commercial Black Powder cans, which I would prefer, but they no longer seem to be on the shelves or available through the websites. So I will have to make do with those things I can get.
ofitg
03-20-2013
Quote Originally Posted by Texantothecore
One of the reasons I like the CIA method is that you can mix a pound at a
time rather than the 4 to 6 oz. that you get out of a straight ball mill
operation.
When cooled to 0 degrees C (32 F) one liter of water is still capable of carrying 133 grams of KNO3 in solution -
http://en.wikipedia.org/wiki/Potassium_nitrate
As I understand it, a drawback of the CIA process is that even if the frigid alcohol cools the slurry to thirty-something degrees, a certain amount of the potassium nitrate will be carried away by the water.
I suppose that extra potassium nitrate could be added to compensate for this loss. I remember one fellow posting that he compared the weight of his finished "CIA" powder to the original weight of the dry ingredients, and it appeared that he was losing about one-third of his KNO3... but that might have been an extreme example... it probably depends upon the ratio of hot slurry to cold alcohol, temperature of the alcohol, purity of the alcohol, etc.
Texantothecore
03-20-2013
I am not surprised at the loss of 1/3 of the KNO3 in the production of bp. Precipitating a chemical is not a very precise method yet it seems to work in this application. I can speculate, however, that the KNO3 is more thoroughly incorporated into the charcoal than with the ballmilling method and most of the charcoal will have KNO3 inside the individual kernels. With the ball method the KNO3 is incorporated but as small kernels which become stuck in the pores of the charcoal.
It may also be that there is a slight difference in the chemical makeup of the remaining KNO3 that keeps it from precipitating out. That would render the saving of the remaining water+KNO3 a waste of time as it might never precipitate out but it might keep the next batch from forming enough precipitable KNO3 to be useful.
In thinking through the sequence of manufacture it also has occurred to me that there might be a fairly narrow range of viscosity (density) in the KNO3 slurry that was ideal and which allowed the crystals of KNO3 to freely attach themselves to the charcoal as well as to form within the charcoal itself. The guy who invented the steamed KNO3 method measured everything and I suspect that may be part of the story but I am having trouble finding any resource that goes beyond the headline "Steamed Gunpowder!" so I do not know yet if that viscosity (or density) might be a factor.
There is only a certain amount of oxidizer that will be used in the conversion of charcoal to gas, heat and remaining solids and after that point the additional oxidizer is not needed. The wet method seems to work well and it appears to deliver adequate oxidizer to the charcoal, so I am not too worried about it.
It is times like this, and there have been many, when I wish I had a degree in Chemical Engineering.
Thoughts after the original post:
In most of the CIA write ups I have read the cooled down mix is put in a sock or other material suitable for straining and then twisted tight to remove the water. It occcurred to me at the time I first read it that the unprecipitated KNO3 would be removed during this time and would be lost. At some point why don't we try to simply pour all of the slurry out and let it dry. The KNO3 that is in water suspension should be then be made available as an oxidizer. This will incorporate all of our KNO3 in one form or another into the powder. It may require a lipped vessel to keep it from flowing over the edges of the drying surface and will definitely require more drying time, but it just might be worth it. On the otherhand, it might make no difference at all (most likely).
The unprecipitated KNO3 would form crystals on the surface of the slurry and it would be best to throw the dried slurry into a ball mill and run it for 15 minutes or so to mix it in with the original green meal.
A better method might be to go ahead and remove as much water as possible through a strainer sock or other material but to capture the water in say, a tupperware container and set the container out to dry. After the green meal and the KNO3 were dry, simply scrape out the KNO3 crystals from the tupperware container and remix the crystals with the green meal in the ball mill (maybe 15 minutes). All but a very little KNO3 should be present in the finished green meal.
Yet another project and I grow more desperate each day for a chrony. But a press comes first.
ofitg
03-20-2013
TTTC, I share your belief that incorporation down at the molecular level (ie, precipitation) should be finer than mechanical incorporation... the ancient Chinese method intrigues me because the cooled water remains with the sulfur/charcoal/KNO3 mixture; it gradually evaporates away, leaving the last bit of dissolved KNO3 behind...
Thanks for posting that info on the Confederate manufacture, it's the first time I ever heard that they were employing a type of precipitation process.
Texantothecore
03-20-2013
Wow! Your comments on the chinese method are great! That would probably be the best way.
I was surprised when I first read the description of the Confederate method, as sketchy as it was, but it did seem to produce some great BP and it was obviously very close to the CIA method. I would love to find out how they processed their charcoal as that may have also been a bit different. Most likely a finer grind.
Assuming that one uses the Chinese method it seems to me that a short run in the ball mill after the green meal dries would be a great help to distribute and even out any uneveness in the distribution of the oxidizer.
The DOD has a huge amount of research on BP and I suspect that there are a number of full write ups on the Confederate method but I just have not had the time to access those papers.
John Boy
03-20-2013
I was wondering what the effect would be if I did not corn my homemade bp that is to be used in .45-70 cartridges. I will be using dextrin in the mix.
Texan, after 109 posts, did you get your post answered and what do you plan to do?
Texantothecore
03-20-2013
I think you could pour your hot green meal into one of those cheap aluminum food pans that most grocery stores sell in their baking section for about 65 cents and place the pan in a cooler with ice in it and I suspect that the ice in your ice box bin would be enough to cool it down. I did a search for dry ice and came up with nothing useful as they apparently stopped selling it but it would really be ideal for a fast cool down.
The thin aluminum pan would be perfect as the heat conductivity is extremely high and it would cool down rapidly with ice or dry ice.
After the cool down, you could place the aluminum pan on your Workmate in the back yard and turn a fan on if there was no wind to help you dry the green meal out. I would not run the fan overnight just as a safety precaution.
After the green meal is dry, empty the pan, break up the green meal and run it in the ball mill to remix the oxidizer and after a short while you have great green meal.
I believe that we are just about there.
Texantothecore
03-20-2013
Quote Originally Posted by John Boy
Texan, after 109 posts, did you get your post answered and what do you plan
to do?
Yes but it has bloomed into something entirely different, which is a common benefit of this board.
I am collecting stuff now to make my own bp. Checking scrap yards for scrap parts, looking at work arounds and contacting some of my friends who might like to get in on this. The objective is to put together a small system suitable for home use which will cost each of us less than two cans of BP. Maybe 40 to 50 bucks.
Maybe less. I have some friends that might have the press at present, etc.
ofitg
03-20-2013
Quote Originally Posted by Texantothecore
Assuming that one uses the Chinese method it seems to me that a short run in
the ball mill after the green meal dries would be a great help to distribute
and even out any uneveness in the distribution of the oxidizer.
I have made a number of small (two-ounce) batches with a variation of the Chinese method. Since each batch contains 1-1/2 ounces of KNO3, I only add 3/4 ounce of water to make the slurry. When the slurry gets bubbling hot, I pour it into a large Pyrex baking dish (not a cool marble slab).
It only takes about one second for the slurry to start cooling and congeal to "ketchup" consistency. I set a small desk fan blowing into the dish and periodically stir the sludge - within a couple of hours, the sludge has dried enough to start "balling up" - after sitting under the fan overnight, it's just about totally dry.
Texantothecore
03-20-2013
Boy is that instructive. I will use that to keep my slurry in good working condition. Thanks for the field info. The actual precipitation probably takes place within seconds of pouring into the dish and then stops because it cannot physically move in the ketchup consistency green meal.
ofitg
03-21-2013
TTTC, I found an online book which provides some details on the Confederate precipitation process - see chapter 12 -
http://books.google.com/books?id=7n6...0steam&f=false
Texantothecore
03-21-2013
Thanks for the link, very interesting. The last four pages of chapter12 are unavailable which seem to be about the process after the initial mixing. If anyone has the book could you scan the last four pages?
It appears that the confederate bp had high standard deviations and high extreme spreads.
Ofitg, a 5 ton incorporation roller was mentioned. Any idea as to what that machine was and did?
I think that authors felt that inconsistent density was the problem that generated the high standard deviation. This was noted with artillary charges which are more precise than small arms but was not noted with rifles. Oh those last pages! So close...
ofitg
03-22-2013
From what I've read of the modern-day process, the constituent ingredients are ball-milled seperately, then piled together and moistened with water. The moist mixture is then incorporated by running 10-ton steel wheels over it for a few hours. Next, the "wet cake" is loaded into a hydraulic press and subjected to 1200 psi, compressing it from 1-1/4" thick down to 3/4" thick. After drying, the "press cake" is granulated.
It sounds like Rains used the precipitation step to do the initial incorporation, and then followed up with a single hour (instead of the usual four hours) under the heavy steel wheels.
On page 246, the book mentions that Rains decided to delete the "compression" step... this might account for some of the inconsistencies... and as the book notes, other production short-cuts (as well as questionable raw ingredients) might have been factors. Those were desperate times for the South.
Texantothecore
03-22-2013
It appeared to me that they did short circuit the compression process and ended up with BP that had high standard deviations. Apparently the stories about the superiority of the Confederate powder came from the developer of the method and no one else. It was used for artillery practice after the war and was a not as effective as could have been: The artillery charts did not apply with this powder and the precision required for artillery was much higher than for small arms. It is possible that the initial powder was quite good but as they shortened the manufacturing process to increase the powder out the door the quality control went out the window. It happens in time of war.
Interesting book, all around. Thanks for the link.
Texantothecore
03-22-2013
I just scored 12 inches of 3" PVC pipe from a friend who is in construction. Free powder dies! Woohoo! That is 15.00 bucks less for the fixed cost.
Texantothecore
03-22-2013
I have decided to pay a lot of attention to the charcoal as that is the explosive in the black powder and will sift it through a 325 screen to ensure that it is air float which apparently is the best method. Although I am trying to keep this process as simple and as cheap as possible I think the extra care in this step would give us a lot more chance for immediate success which may be important to the other guys in the group.
Since I will have that 325 screen would it be worthwhile to process the sulfur and the KNO3 to the same "air float" granular size?
Your thoughts on this would be appreciated.
Mcmaster-Carr:
Type 304 screen, woven 12" x 12" section, 325 x 325 mesh size
P/N: 85385T115 $13.12
ofitg
03-22-2013
Correction to my previous post - the incorporated mix coming from the heavy steel wheels is called "wheel cake", not "wet cake"... brainfart... too many Graveyard shifts...
I saw something interesting in that book - it mentioned that the compression step causes sulfur to become colloidal and encapsulate the other ingredients. I hadn't heard that before.
Regarding the need for "airfloat" ingredients prior to mixing, I have my doubts that it's really necessary. I believe most modern home-brewers incorporate their powder by ball-milling all three ingredients together for several hours.
Since I started playing with the Chinese precip method, I ball-mill the charcoal and sulfur together (no need to ball-mill the KNO3 since it's going into solution). After several hours in the ball bill, the dry ingredients are probably close to "airfloat" anyway.
Since you're planning to include the 1200+ psi compression stage, you can probably count on the sulfur going colloidal. The size of the original sulfur particles might not matter... at least that's my guess. As you experiment with your process, trying different ideas, you'll determine the best way.
Texantothecore
03-22-2013
I am looking forward to the experimentation as it is a large part of the fun.
I am going to drop the screening of premix components as it is probably a control level that is not needed. I think you're right about the components being air float after having been milled for several hours and that should be just fine.
It would have turned out that I would have timed the milling anyway and used that time for the milling and the screen would have been used just once and then put aside.
Texantothecore
03-23-2013
When you boil the KNO3 how much of it actually dissolves? I would make a guess that most of it does not dissolve although your statement that a liter of water will hold 4 ounces makes me wonder about it. That is a lot dissolved in the water and that is what intrigues me.
I was surprised to see that as the technical information describes KNO3 as only moderately soluble in water.
ofitg
03-23-2013
Here's some solubility data for KNO3 (on the right side of the page) -
http://en.wikipedia.org/wiki/Potassium_nitrate
At 32 degrees F, one liter (1000 grams) of water will dissolve 133 grams of KNO3.... that's 13.3% of the water's weight.
At 212 degrees F, one liter of water will dissolve 2460 grams of KNO3... almost two-and-a-half times the water's weight.
Texantothecore
03-23-2013
I didn't see the panel on the right of the Wiki reference. That is a lot of KNO3 to dissolve. I could probably go with prilled KNO3 at that high solubility in water. It should disappear quickly in boiling water.
ofitg
03-23-2013
When I'm preparing a slurry, I use a quantity of water equal to half of the KNO3's weight; that provides a little allowance for water lost to evaporation.
Texantothecore
03-24-2013
Quote Originally Posted by ofitg
When I'm preparing a slurry, I use a quantity of water equal to half of the
KNO3's weight; that provides a little allowance for water lost to
evaporation.
Thanks for the info. 16 oz of water per pound of KNO3 it is.
Texantothecore
03-25-2013
I read through the Foxfire #5 and there was not as much on black powder production as I had thought. It did have great instructions for leaching KNO3 from human and cattle feces. I think I will leave that alone for the moment as the stench and mess would be uh... monumental. A real conversation starter in your subdivision. LOL.
One thing I did notice is that one of the techniques they used was to keep it in water for 10 months. If there are a certain type of bacteria in the mix it could reduce the nitrogen content due to the bacteria utilizing the nitrogen through an anaerobic reaction. This reaction is a problem in farm fields that are flooded for more than 10 days and sometimes the farmer has to reintroduce nitrogen to the soil because of depletion. But I am not sure as this is sheer speculation.
Texantothecore
03-25-2013
I have about 40 lbs of hard wood untreated chunk charcoal and this weekend I will take about 4 or 5 pounds of it, put it in a spare charcoal bag (rather tough) and run the car back and forth over it to see how far down I can reduce it. I will then take a look at it with magnification and see what I have. Probably no 100 screen particles but I am hoping that I will be surprised at the level of internal grinding and shearing of the pieces of charcoal.
I am hoping that the charcoal will grind against itself and reduce at least some of it to a size that is more useful and a heck of a lot easier to grind in a grain or coffee mill. I will report back here on the results.
I will repeat the test later when I have screens in-house and report on the results with some statistical analyses. This first test is more of a feasibility test to see whether it is going to give me some useful results.
Texantothecore
04-04-2013
I have been doing a bit of research on safety in making black powder and I would like to address that issue:
Most of the accidents fall into two categories:
1. People who mix and make their own rocket engines. I am not at all sure why there should be a number of accidents in this area but it seems to happen, though rare. I am aware of some of the differences between rocket engine fuel and our small arms black powder and this may account for it.
2. Factories which blow up when engaged in the production of black powder. I spent 35 years in manufacturing, some in very hazardous atmospheres and it struck me after thinking my way through it that factories are very different than your garage, your backyard or your basement. There are nearly always sparks present from worn commutator brushes and various other machinery malfunctions such as worn out bearings that could light off dust and create fires. Some of the factories in which I worked did have small fires and management took the opportunity to teach everyone including the administrative staff the skills used to fight small fires and at least delay their spread.
In most of our operations in our homes we don't have anything like that and I think, and this is just an opinion, that the average garage is quite safe if you eliminate sources of sparks and fire which is pretty easy to do. Just the air movement from leaving your garage door open when you are working on the black powder is probably vastly superior to the ventilation of most factories and it should be quite safe.
We have not had a lot of powder mills in this country and it appears that the reasons for it is that it is probably more profitable to mill grain than it is to mill powder and so many people made their own it just did not make economic sense to set a mill up. It is possible that millions of people made their own powder without incident over the last 600 years.
Most likely it is as safe to make it as it is to handle it out of the can.
So just some thoughts on safety that might be of interest to you.
Boz330
04-04-2013
I am hoping that the charcoal will grind against itself and reduce at least some of it to a size that is more useful and a heck of a lot easier to grind in a grain or coffee mill. I will report back here on the results.
I will repeat the test later when I have screens in-house and report on the results with some statistical analyses. This first test is more of a feasibility test to see whether it is going to give me some useful results.
Hard wood is going to make a really slow powder. I grind mine up in a #10 meat grinder and it does a pretty good job. I then mix everything in the ball mill and it seems to finish the pulverizing process.
Texantothecore
04-05-2013
Quote Originally Posted by Boz330
Hard wood is going to make a really slow powder. I grind mine up in a #10
meat grinder and it does a pretty good job. I then mix everything in the ball
mill and it seems to finish the pulverizing process.
The test is more to determine whether just running over will do some reduction or whether it isn't worth the little trouble involved. It also will tell me whether I can do some reduction of 5 or 6 pounds of charcoal in a few minutes for future use. The softer charcoal should reduce further down than the hardwood but this test should at least give me some indication as to the efficacy.
I don't expect to use the charcoal for blackpowder as it would indeed be too slow.
It will also keep me off the streets until I find my meat grinder. It is currently missing and I am hoping to find it soon.
cal50
04-05-2013
Making rocket engines is usually one of two methods.
Production methods usually use a press and spindle arrangement. After a nozzle is formed the BP is added and pressed on a spindle to compress the BP.
The other is had ramming BP into the rocket motor case using a mallet and hand tooling. The type depends on the application and if it's a end burning or core burning engine. Tamping or ramming flammable propellants has self explanatory safety concerns.
Hundreds of pounds of BP was hand tamped in bore holes for quarry blasting & mining. Once in a while if the metal tamper hit hard rock the tamp rod comes out of the bore hole quickly followed with fire & smoke...
cal50
04-05-2013
If you start cooking your own charcoal a good way to quickly rough grind it is using an old garbage disposal. Charcoal in the top and fine charcoal out the side tube. It works good but grinding charcoal is still messey at best.
Texantothecore
04-05-2013
Quote Originally Posted by cal50
If you start cooking your own charcoal a good way to quickly rough grind it
is using an old garbage disposal. Charcoal in the top and fine charcoal out
the side tube. It works good but grinding charcoal is still messey at best.
I have the feeling that my darling wife sort of arranged for that nasty meat grinder to leave the premises during one of her garage sales. But I do have some friends from small towns in South America who may have an old Corona grain mill which is what I would prefer to use. I'll have to talk with them.
The mess from just running over the charcoal with the car would be a lot less than some other methods. I will probably try it sometime this weekend if I can find the time.
Texantothecore
04-05-2013
I just ordered some screens from McMaster-Carr. I will be posting some results as soon as they come in.
Texantothecore
04-10-2013
The screens came in yesterday and I am ready to go on the test. It is going to rain today so the testing will be delayed.
I ordered 325 and 100 screens and boy are they smooth. Those holes are really tiny.
Well, the test will tell me something about the charcoal and how it reacts to pressure. I probably will be doing other tests as well to learn the characteristics of the material.
RMulhern
04-11-2013
You can 'corn' or not... or you can say Our Fathers and Hail Marys over it but in the long run... you're only gonna get a consistent 1 1/2 to 2 MOA accuracy out of it!
Texantothecore
04-11-2013
We'll see how it goes. I started out with muzzle loaders and shot those for years. When I went to cartridges I used modern powder and have done the super accuracy stuff for about 7 years.
I decided to return to black powder this year and the magic is back! Woohoo...
cal50
04-11-2013
Quote Originally Posted by RMulhern
You can 'corn' or not... or you can say Our Fathers and Hail Marys over it
but in the long run....you're only gonna get a consistent 1 1/2 to 2 MOA
accuracy out of it!
Not entirely true or accurate. Depending on the manufacturing process, consistency and quality of base indegridents the powder can be much better or worse than commercial propellants. Very basic chemistry and mechanical processing involved.
Texantothecore
07-01-2013
I just picked up 5 lbs of Eastern Cedar bedding at petsmart for 8 bucks. It should produce some good powder. I can't wait to get ready.
cal50
07-02-2013
Sounds like charcoal cooking time...
Texantothecore
07-03-2013
Indeed. I just picked up a brand new paint can at Lowes and the balloon is about to go up.
This is going to be so much fun.
mold maker
07-03-2013
Get ready for black face, hands, clothes, and shoes. Oh yeah the whole area. When you get it ground, be sure not to sneeze.
Don't ask.
cal50
07-03-2013
If you want to compare the mess drop 100 lb. bag of airfloat charcoal from your attic on the garage floor.
It's not pretty.
Texantothecore
07-13-2013
Thanks both of you for the heads up. I am trying to enclose any activities in order to limit the distribution of charcoal to the target containers.
Texantothecore
07-24-2013
Tractor Supply seems to have some galvanized steel utility cans which, depending on size, go from 10 to 20 bucks a piece. 6 and 10 gallon cans lured my interest. They come with lids so they could be good for producing charcoal.
Tractor Supply:
10 Gallon Behrens Steel Utility Can with Lid:
SKU 6010605
$19.99
6 Gallon Behrens Steel Utility Can With Lid:
SKU 2220177
$14.99
Both of these willl make a lot of charcoal.
I looked up "behrens" on the Lowes sight and they have smaller selection and are just a bit more expensive.
Texantothecore
07-29-2013
Has anyone tried to wrap wood with heavy aluminum foil, placed it on a cookie sheet and baked it to perfection on their bbq grill by controlling the grill temperature?
It seems to me that it might work.
Nobade
07-29-2013
It seems like it would reduce it to ash. The reason for putting it in a retort is to keep the air away so it doesn't burn.
Boz330
07-30-2013
My first batch I put the retort in an LP Brinkman smoker but didn't try to control the temp just ran it on max. Heat loss with that setup would be pretty high and the burner output isn't all that high. If you insulated it though you might be able to do a better job controlling the temp. I believe that the real secret to consistent powder is the CC.
I have seen articles on the curing temps but don't remember where.
cal50
07-30-2013
Quote Originally Posted by Texantothecore
Has anyone tried to wrap wood with heavy aluminum foil, placed it on a
cookie sheet and baked it to perfection on their bbq grill by controlling the
grill temperature?
A paint can or ammo can works better, just poke a hole in the lid. You need something that seals up decent. The ammo can will smoke if you leave the rubber gasket or until it burns off. Paint cans can be had from a Sherwin Williams or pant supply place. Place wood in can with lid, place on heat source and heat until no more smoke. One removes from the heat source flip the can over with the hole side down or against some dirt to seal it up and keep air from entering the can and burning your new charcoal up.
Texantothecore
07-30-2013
Nobade, I think you're right. Thinking about it last night I couldn't figure out how to really seal it tight and that would yield some nice ash. I figured that the offgassing of volatiles would open up the sealed edges of the foil and invite air in as the charcoal cooled thereby setting it on fire.
Back to the paint can.
I am going to chuck up a small piece of aluminum rod in my drill, take a file to it and make a conical plug that will drop in the lid hole to keep air from entering during the cooling phase.
Nobade
07-30-2013
I just use a pin punch. Made of steel, tapered, seals the hole nicely. Ends up covered on black goo but I only use it for this so I don't mind.
Texantothecore
07-30-2013
That sounds like a great idea. It has the added benefit of using tools in ways that were never intended, such as using a screwdriver as a pry bar.
Texantothecore
09-25-2013
I am about to order my Thumlers Tumbler and wondered if y'all had a preference between the high speed (40 rpm) and the low speed version(20 rpm).
I do not tumble brass and my suspicion is that it probably doesn't matter. The other tumbler possibility is the A-R16 which runs 9 pounds rather than 15.
Your thoughts on this?
Nobade
09-25-2013
High speed for sure.
Texantothecore
10-11-2013
My pressure gauge is on the way in and I was wondering if you used packing in the threads of the gauge fitting in order to seal it a bit tighter.
cal50
10-12-2013
Teflon tape.
Texantothecore
10-16-2013
I am having a bit of a problem getting eastern cedar to convert to charcoal.
I am using gallon paint cans in a grill (small) and the bottom third or half converts nicely while the top section dries out. Currently I am removing the can after it stops offgassing, letting it cool, opening it and compressing the top half into as tight a column as possible, returning it to the fire and it then converts without any further problems. I have found, however that the empty top section is not a problem so it may be that I can just fill the can to half full and go with that technique. Any insights would be welcome.
I am using shaved eastern cedar (horse bedding).
Boz330
10-16-2013
Probably insulates itself too much. I would think that branches would work better, but do you have eastern cedar down there? I just recently tried some Tree of Heaven and was getting more feet per second from it. I have both trees in abundance on my farm though.
Texantothecore
10-16-2013
Yes we do have eastern cedar in Texas. I used to live on a ranch that had a lot of it and I am going to stop by there one day and pick up some dead branches.
I think you're right about the insulating properties. I am looking now for a wide shallow pan that would allow the wood to be nearer the heat. The current method is definately workable but I would like to convert the cedar to charcoal a bit faster.
I am thinking about setting the gallon paint can in a five gallon can with a hairdryer attached to get higher temps, so it is a work in progress.
Texantothecore
10-23-2013
I had a nice surprise last night. I spent last week learning how create charcoal using the eastern cedar horse bedding and finally succeeding after a bit of trial and error.
Over the last couple of days I ran my a-r6 tumbler for a total of probably an hour and a half with charcoal in it from last week plus about 50 .490 roundballs for grinding media. I opened the grinding tub expecting to see a good amount of charcoal which had not been ground down but what I found appears to be airfloat charcoal, every bit of it.
Wow. The Tumlers Tumbler does a great job, far beyond my expectations.
This is turning into a lot of fun with new discoveries each time I do something.
Boz330
10-25-2013
Texan, have you read the BP sticky over on the ML forum, a lot of good info there? Pretty long though.
Texantothecore
10-25-2013
I've read through it twice but not since I have started the process. I will do so again as i suspect many of the points will have a different meaning to me. A very good suggestion, thanks.
I had thought that my plans to use prilled KNO3 would require a grain or meat grinder to reduce it but the guy who deals the KNO3 said that a ball mill is entirely adquate to reduce the pellets to very small grains. Considering the grinding action of my tumbler it appears that it will work beautifully. My concern was whethet the pellets had some elasticity and would deform but it appears that they will shatter quite well.
One of the attributes of the eastern cedar that was very noticable when I was transferring it to the tumbler was that the pieces that were whole were much softer and fragile than I have seen before with hardwood and they broke with very little pressure. I haven't seen charcoal this soft before and it is a bit odd to see it crush so easily
Texantothecore
10-25-2013
It has also occured to me that a 5.50 inch steel plate in the top of the paint can could be used to compress the wood as the conversion took place and would eliminate the need to pull the can off the fire to compress it.
An additional thought would be to use a straight sided gallon can and cut a round steel piece to fit reasonably closely and compress thoughout process. I am not sure a fixed top is really needed if you compress frequently driving out the oxygen. So there are some possibilities for innovation here.
My press is going to be in-house this next week and I am going to press the cedar to much higher densities before it goes on the fire, so that should help a bit too.
Boz330
10-28-2013
I make my powder mostly for deer hunting. I built a Rolling Block from a 1874 Swede 8MM action that had the tang welded and a 40-65 barrel with a 18 twist that came off of another rifle. I did splurge a little on a Tree Bone stock for it.
The picture is 3/4 scale steel deer silhouette. I shot 5 rounds at 50yd off hand, another 5 from 75yd sitting and 10 rounds at 100yrd sitting. The load is 52gr of HM (which is a case full) under a 325gr 3/4 meplat boolit. It clocks in at 1250fps. 2 shots were called right and 1 low. All but the low shot would have gotten the job done. There is just something satisfying about making your own powder, boolits and gun to fill the freezer.
Texantothecore
11-06-2013
I had a real breakthrough last night in producing charcoal using a paint can.
I put the can on its side on top of the coals as the heating area of the side is twice to three times the bottom area. I had a normal amount of smoke and gasses but after the smoke started to peter out I turned the can 180 degrees and the smoke immediately went to levels I haven't seen before. It was jet that lasted a while and after the smoke stopped I turned the can 45 degrees and again a large jet appeared. The next move was to turn the can 180 degrees to get the last quarter heated. Again a jet for a short period of time. I opened the can after it had cooled and it appears to be a full conversion to charcoal.
I added another layer of charcoal, squirted lighter fluid on it and immediately placed a new can on top that had nearly twice the amount of cedar as the first. I had compressed the cedar using a delrin flat and I had great hopes to increase output. I was not disappointed as the can began offgassing within two minutes as opposed to twenty or thirty minutes. When the smoke stopped I turned it and the plume coming out of can was unbelievable.
A couple of turns later I took the can off set it aside to cool. I fully expect to see full conversion when I open it up tonight. The second can took much less time than the first and a lot less charcoal.
It appears that most of the conversion occurs after the first turn and the additional quarter turns quickly clean up any unconverted wood.
Although I will continue to experiment to increase production it appears that I have a good working method for those of us who have to use small bbq pits.
One happy camper here.
Boz330
11-06-2013
I'd be interested in your results with the Cedar, velocities and groups, when you get done testing. I recently made some Tree of Heaven CC and the powder produced 50fps more than my Black Willow CC in the same round. The velocities were higher but much more ES but the groups at 100yrd weren't really to bad. But my criteria is minute of deer to 125yrd max.
Texantothecore
11-06-2013
From what I have read cedar should do quite well.
I don't have a chrony yet but it is on the list. Maybe I can borrow one for testing here in Katy at some point.
This is going so well I can't believe it.
Texantothecore
11-06-2013
A couple things I learned last night:
1. Put the can sideways on the fire when you first light it. Apparently the lighter fluid is very hot and will bring the paint can up to working conversion temperature in about two minutes.
2. At various times I squirted more lighter fluid on the fire and the offgassing immediately increased. So the conversion can be well controlled with cheapo lighter fluid.
3. The conversion responds immediately to increases in temperature with much faster conversion rates. Which leads me to believe that a simple modification to my tiny barbeque (12 inches?) to allow the attachment of a small hair dryer for forced air might be the ticket to a very high conversion rate.
4. Use of a screwdriver or chisel to open the paint can will damage the lid. Buy a couple of paint can openers as they are designed to work without damaging the lid.
Texantothecore
11-07-2013
I opened the can of compressed cedar last night and found that there was a core in the center of the can, maybe 1 inch to an inch and a half wide, which had not converted. I have a great deal more charcoal from this can than I did with the less compressed cans but it looks like I will have to leave it on the fire for more time or increase the heat.
Friday night I will take my cans of charcoal and pour them into my ball mill and run them for six hours or so. I am really looking forward to seeing the results of my handiwork and using some homemade powder.
Monttexan
11-07-2013
I just read through this entire thread over the past couple of hours and have a question and a couple of comments.
I never saw where anyone answered the question whether or not Birch wood will make good charcoal?
There was a comment about being unable to find dry ice for cooling. You should be able to buy dry ice in any decent grocery store. I haven't needed any within the past 6 months, but have bought it within the past year.
Part of the safety discussion at one point involved comments about grain silos blowing up. When silos explode it's a particular type of reaction. If I remember correctly it's called a colloidal explosion. Basically, each dust particle is completely surrounded by air and can then ignite. No, I don't remember all of the specifics; I learned about it in high school chemistry class and that's been a while! We did make a flour bomb in class though. WE put a small amount of regular white flour inside a metal can with an alcohol burner. A blast of air was shot up underneath the flour via a hose to suspend it in the air, and boom, the lid of the can blew off! It's the suspension in air that makes it dangerous. Similarly, I've done the test, though don't recommend it that you can throw a lit match into a small puddle of gasoline and it will put the match out. Gasoline vapors are more volatile. All this long-windedness is about your fine charcoal dust being flammable, but much more dangerous if you let it get suspended in air.
Texantothecore
11-08-2013
It appears that birch has been used for black powder and it may be pretty good. The reason you don't see much talk about it is that it is generally more expensive than cedar. Way more expensive...
The discussion on colloidal explosion was because I have worked in a number of industries in which it is a factor but it is no longer a threat due to the use of electostatic precipitation systems that clean the air rather well. In any case, an open garage door is better than the still air of 99% of factories so it should not be a factor at all.
The airfloat charcoal is not nearly as difficult to handle as I had thought it might be so I am quite satisfied with the setup.
Texantothecore
11-08-2013
I just loaded the compressed cedar can into the tumbler and it turned out that the unconverted cedar was a shallow area and I did get nearly complete conversion. So the technique I used really worked quite well, fast and with fairly high production.
Boy do I have a lot of charcoal. It will keep the press humming for a while. Lol.
Texantothecore
11-11-2013
The birch appears to be too heavy, about the same as oak, and it will probably be too slow.
Most of the woods listed as good bp charcoals are about 27 lbs. Per cubic foot or so. Any wood around this number or lighter should work ok.
Engineeringtoolbox.com has a good list of species and their weights.
Texantothecore
11-13-2013
Some questions for our experts:
1. I will be grinding my charcoal down to airfloat over the next few days. It is currently reduced to 16 or 18 screen for storage. I expect a six hour run in the tumbler will get it down to 350 size screen for airfloat.
1. I am using Spectracide for the KNO3. Should I airfloat it as well as the garden sulfur before the final mixing and grinding run?
2. I am expecting to expend 6 hours on the final mixing run. Does this match your experience? My current set up is a Thumler with one pound of .490 roundball and two pounds of 405 grain .45-70 boolits. It grinds very rapidly.
3. I will be picking up my 12 ton press on Friday. Are there any pitfalls or traps to watch for when I take the hydraulic cylinder apart to drill and tap it for the pressure gauge?
Boz330
11-14-2013
I grind my CC in an old meat grinder, then put all of the ingredients together and ball mill. I have a Harbor Frieght tumbler which doesn't work as good as the Thumbler but gets the job done. The Thumbler is so big and I don't normally make that big of batches. Can't help you on the press, I just use a bench vice. Big problem is probably getting all of the chips out of the jack.
Texantothecore
11-14-2013
Both my monster bench vise as well as my meat grinder went out the door during a garage sale so I have had to replace those with some more equipment that turns out to be better suited to the tasks at hand.
I would love to drill and tap the hydraulic cylinder in place as I cannot find a schematic of the press anywhere but it looks as if I will have to take it apart to do the project. I have no idea what is inside the cylinder but looks as if I will become expert on the construction of this press
The reason I bought the Thumler was not the capacity but the thermal cut off on the motor which will shut it down if the engine overheats. The fast grinding that I have seen is just icing on the cake but I think that the Harbor Freight ball mill is quite good. You can tell I was in mfg for 35 years and that I attended every safety meeting offered.
Your comments tell me what I need to know about the final run and I thank you for your reply.
Texantothecore
11-20-2013
I am getting, by weight, 30% charcoal which is a bit of a surprise as I thought it would be closer to 20%. A nice surprise.
cal50
11-24-2013
Quote Originally Posted by Texantothecore
That video does a great job in explaining the process. Going to get it
going in the next week or so.
The structure of the hydraulic jack is very different than I had thought, a real education in that video.
The other link has some good info on how to calculate the actual force.
Using a gauge is the only way to be repeatable and have consistent results.
Texantothecore
12-06-2013
I can't seem to find nipples that will withstand 6,000 psi. Any ideas as to suppliers? This may be a matter of searching with wrong words but I haven't found any high pressure pipe or 90 degree elbows yet.
Nobade
12-06-2013
Do you have a hydraulic repair shop in your town? They should have what you need.
Texantothecore
12-06-2013
Sheesh. Of course. I will try them.
Texantothecore
12-13-2013
I found a great store not too far from my place and the guys are very knowledgeable and the fittings are way cheaper than I expected. Cheap enough that if I want to change the configuration I can do so with pocket change.
Cal, how thick is the base plate on the cylinder? I am going to be taking the hyraulic cylinder apart next week and drilling.
I am also thinking of drilling through the bottom, installing a right angle fitting and bringing a hose (9600 psi) out the side through a hole drilled in the skirt. I will probably go shopping today to see if the parts are available.
If the parts stick out beneath the bottom skirt I might be able to use a Delrin spacer between the bottom of the skirt and the jack plate to allow the additional room needed for the fittings. Does that sound reasonable?
cal50
12-14-2013
Thickness varies with the jack brand and tonnage but nothing too thick a standard length drill bit cant handle.
Hole placement is really up to you and depends on how you are setting your press up. The one thing I did not do is get a cut off valve for my pressure gauge. I was pressing out some wheel bearings and ran almost ran my gauge out of range before they broke loose. Its nice to have but not necessary. I have a gauge that is smaller graduations and total PSI and easy to read.
Faret
12-21-2013
How much water is everybody using to press their powder. I have heard anywhere from 4 - 8% by weight.
Nobade
12-21-2013
Quote Originally Posted by Faret
How much water is everybody using to press their powder.
VERY little. I don't know the % by weight, but I have worked it out so that my die holds 6 heaping teaspoons of mill dust moistened by 5 shots from my pump spray bottle. That is not much water, when stirred in it just starts making the powder clump into balls. The deal is to adjust the water so that the pressed puck is uniformly moistened but no water runs out of the bottom of the die. If water runs out you are losing nitrate and the powder isn't as good.
Texantothecore
12-21-2013
The number that I consistently see is 6% by weight which apparently works quite well and produces Bp that sticks together well.
Texantothecore
12-21-2013
Hobby Lobby has round wooden needlepoint frames to stretch fabric tight and I picked up three of them to use with my screens from Mcmaster. $1.74 per piece. The cost benefit ratio is really extreme on this piece of equipment. I lay the screen on the inside frame, push down using the outside frame and tighten to taste. Easy as pie.
Hopefully I will get back to some processing when we get some clear weather. Since I dumped some airfloat charcoal on the off-white living room rug I have had to move my act outside. A product called "I Love My Carpet" takes out the charcoal after you have vacuumed the majority up. Phew... I was starting to sweat over this incident.
Texantothecore
12-21-2013
A tip for those who use the Thumler Tumblers. The drive belt is very loose but works like a charm to turn the tumbler. The drive belt on mine began to malfunction and slip on the pulleys and when I looked at it there was a small amount of charcoal on the drive belt. I washed the drive belt with Dawn and water, wiped the pulleys clean, remounted the drive belt and it now works as manufactured.
Texantothecore
12-21-2013
With all the rain we have had I have taken a bit of time to look at the hydraulic cylinder and it appears that I won't need to go throught the bottom, but through the side. There is a flat area on the base which appears to have no structural function but which is designed to be a flat surface useful for attaching pressure gauges and such to the jack. If you look at the bottom of the jack there is a rib of additional steel that meets this flat area and it appears that the drilling will not require the amount of precision that I had thought. In short, there is plenty of steel to drill through. Good news for this desk jockey!
By the way, the brand of press I am using is the standard Harbor Freight 12 ton press made by Central Hydraulics.
Texantothecore
02-08-2014
The final numbers for the charcoal are in and they are surprisingly high.
Eastern cedar (bedding from Petsmart)
Weight 75.2 oz
Charcoal weight 27.2 oz
Yield 36%!!!
This should be enough for 10 lbs of black powder.
People, this is well worth the effort. I am thrilled with these results.
cal50
02-10-2014
That is a good supply and should last a while.
Texantothecore
02-11-2014
Now to turn it into useful powder. Next up is to drill the hydraulic cylinder and install the pressure gauge.
Can't wait to get the finished product up and running.
Faret
02-11-2014
Think 3000 psi is enough using the harbor freight 12 ton ram and a 3" die?
Texantothecore
02-11-2014
3,000 psi on the gauge = 879 psi on powder
4,000 psi on the gauge =1171 psi on powder
5,000 psi on gauge = 1463 psi on powder.
Since commercial is compressed at 1200 psi, 4,000 gauge pressure might be just perfect.
Faret
02-11-2014
Thanks just what I wanted to know! Once it warms up or mother nature gets off the rag I am going to press me some!
Texantothecore
03-19-2014
On my current batch I am incorporating the bp in a ball mill. About 1 hr away from full incorporation and I can't wait to test it.
The batch is twenty ounces and I hope it is not too much to run in this ball mill (thumler ar6) for this step. Probably overthinking the process.
Texantothecore
03-19-2014
Quote Originally Posted by cal50
That is a good supply and should last a while.
It is my hope that it is not going to last very long and that I will begin to shoot each week with my caplock rifle and with my new '51 Navy revolver, which is backordered.
I just received 53 lbs of lead and it may be that the lead will be the logistics issue rather than the black powder which will be a reversal for me.
cal50
03-22-2014
If you have good powder, which you will have if you use good charcoal its 1/2 the battle!
Texantothecore
03-26-2014
I finally finished the 6 hour run in the ball mill and it tested slow. It appears that the 3 lbs of 405 grain 45-70 grn bullets are sufficient to grind but may not not be sufficient pound the kno3 and sulfur into the charcoal grains which is what is really needed.
So I'm going to add enough bullets to get the capacity closer to the max of 9 lbs. This should work and is consistent with Fly's contention that the mill should be 1/2 full of grinding media and 1/4 powder.
I will keep you updated after I pour some more bullets, run a few hours and test it.
cal50
03-28-2014
Ball mill effiency is important.
You do not want to over charge your mill. I have a large tumbler drum filled 1/4 - 1/3 with brass lapping balls about 1" diameter. I used a speed controller and my drum rpm is around 50 rpm. I use a timer on the plug in for setting the run time.
I mill my kno3 first for 4 hours.
Add sulfur and mill for a couple hours.
Charcoal added in last and milled for a couple hours.
Once the charcoal is added you have an enclosed flammable solid and set the timer and go away until done.
Texantothecore
03-28-2014
Great explanation of your technique. I have nowhere near that much grinding media in the ball mill. There might be 2 lbs of 405 grn boolits and 1 lb of .490 roundball and it would seem that just isn't enough.
Texantothecore
03-29-2014
My drum is turning at about 20 rpm and it may be that I need to keep it on for a much longer time, say 18 hours rather than 6. What is the diameter of your drum? The thought has occurred to me that the distance the interior of the drum has traveled may be a better indicator of milling efficacy than would be time as it would correlate to the amount of exposure the black powder would have had to the milling media but would be independent of rpm.
Lessee... 7 inch interior dimensions
Perimeter of interior:
7*3.1416 = 21.9912
7200 rotations in 6 hours
7200*21.9912 inches = 158337 inches of travel
158337/12 = 13195 feet of milling
I would be willing to bet that your feet of milling is much larger per batch.
cal50
03-29-2014
I will have to check my notes for the weight I was running but you adjust it to your mill's volume.
My milling time was 2:2:1
2 hours KNO3
2 hours KNO3 + sulfur added.
1 Hour with the charcoal added for a total of 5 hours per batch of powder.
My drum is the Thumler's 15-Pound Barrel:
Barrel Dimensions in Inches
Height Diameter
Inside (min) 8 1/4 6 1/2
Outside (max) 9 9 1/4
You want to charge you mill by volume and not weight.
You should have a milling jar or drum about 1/2 full of tumbling media and about 1/2 full or less of powder you are milling.
Texantothecore
03-30-2014
I added 3 lbs of 405 grn bullets to the ball mill and tried it out for a few minutes. Although it is still quiet it made about 4 or 5 times the sound that it had been making. You can hear nearly continous sound as the bullets fall on the black powder. It is running now with 6 lbs of bullets and 1.25 lbs of black powder. I think I know where another lb of media is hiding and will throw that in tomorrow.
Hope this works.
It is much more violent inside the barrel than before.
cal50
03-30-2014
An efficient ball mill is a thing of beauty.
You can have a barrel of given volume and the amount of milling media and the amount of charge you are milling makes a big difference.
One huge plus is even a poor operating ball mill produces much better results than dry or wet mixing components.
You will be surprised when your 1st mill batch is pressed and corned. Its that "woof" sound of powder and little residue left behind that marks a good powder.
Texantothecore
03-31-2014
I suspect that when I finish the current batch that it will work famously and I am looking forward to it. I was very disappointed with first test but after our discussion concerning ball mill techniques I am thrilled that the first test amount achieved ignition and burned rather merrily.
The interior of the mill is a much more aggresive milling environment with the addition of more milling media. I can hear the media falling in the mill rather than simply rolling over the powder. It is going to take a few days to get to the point of testing and we will make any additional adjustments as needed.
Texantothecore
04-03-2014
Nodda Duma is making good fast powder with white birch. I stand corrected.
cal50
04-04-2014
Its really not that challenging to make better powder than commercial IF you have the basic equipment and good charcoal.
I have been using airfloat charcoal for pyrotechnic use and purchased some nice willow charcoal for my better BP experiment.
The charcoal really is the key element in making great BP.
Texantothecore
04-05-2014
Yup. I'm still about an hour and a half away from a test. Hopefully the expected rain this afternoon will hold off.
cal50
04-06-2014
I did lift testing using my homemade powder and compared it to Goex , Elephant brand and another commercial powder.
I used a 3" mortar tube and made a slug shell (sand inside for weight) and fired it vertical and timed the total time in seconds from ignition until the shell reached max altitude and fell back and hit the ground. My homemade powder WAY out performed all of the once I tested by a large margin.
I used a 25 gram sample for the lift charge. Fun stuff!
Texantothecore
04-07-2014
That is quite interesting. I am going to do much the same test with an empty film can and see how mine performs versus ffg. It should be instructive to say the least.
Nobade
04-07-2014
Baseballs work pretty good for this...
Texantothecore
04-08-2014
I was thinking through my process the other night and after looking carefully at my equipment it occurred to me that the oft heard line "you have a bomb in that ball mill" when the final mix is milling is not correct.
The vinyl barrels that we use will not withstand very much internal pressure. They are also very tightly closed environments which will not allow sparks or fire without opening a hole which will eliminate the possibility of an explosion.
Basically, all you get is a fire that burns quickly and sounds like "whoosh".
Comments?
cal50
04-08-2014
Quote Originally Posted by Nobade
Baseballs work pretty good for this...
I never had a surplus of old baseballs but PVC pipe with a couple caps on the end works well and is cheap. I made a few up and weight matched them and hit them with orange paint.
If the ground is soft it makes a nice thump and sticks the landing. We lost one to a pond...
Texantothecore
04-08-2014
That sounds like a launch enhanced lawn dart, the scourge of subdivisions throughout the land. Lol.
Texantothecore
04-09-2014
The last test this week turned out slow again but faster than before. I am going pull this batch out of the barrel and pack bulk rice with it to make sure that it is dry. Rain has been a real problem.
I am going to use Cal50s milling protocol (page 11) and see if it does any better.
I am still on the front end of this project so it is just a matter of eliminating variables.
Texantothecore
04-14-2014
Home depot is selling 3" PVC pipe in 2 ft lengths for about 7 bucks. No need to spend 15 on a long section of pipe anymore.
The 3" pvc is used for powder dies.
mold maker
04-14-2014
Because it's been an extremely wet Winter and Spring, everything I own is damp. Other than rice (damp also) how do I dry the individual components, to get accurate weights to mix?
I rains a solid day every week and is cloudy a couple more. When its dry, the wind blows.
I'm sure the damp ingredients weigh different.
Texantothecore
04-14-2014
I doubt that it matters. I would go ahead and start making it and make sure it is dry when you finish. Small variations in weight due to humidity shouldn't matter much.
Faret
04-17-2014
Screened some today got about 25% fines that will be pressed again. How did I do? By the way it is FAST!
Texantothecore
04-17-2014
Quote Originally Posted by Faret
Screened some today got about 25% fines that will be pressed again. How did
I do? By the way it is FAST!
It sounds as if you have a solid technique. Congratulations and go shooting!
Texantothecore
04-23-2014
I unloaded my ball mill last night and the green meal is probably the lightest material I have ever seen, really fluffy and full of air it doesn't seem to have any weight. This ball mill is doing the job.
Texantothecore
04-23-2014
I compressed the green meal with a small hand press and it is fast. The first batch is good and true.
Has anyone experimented with varying the press pressure in order to produce different velocities?
cal50
04-24-2014
I always pressed the same amount of material , pressure and dwell time pressed for consistency and repeatability.
You can have a better impact on burn rate by decreasing / increasing the milling time and or the sulfur content.
Add water to your powder then press it.
Just remember even wet powder is flammable.
Texantothecore
04-24-2014
I have never heard of varying the sulfur content in order to change the speed. Bp is quite amazing in its flexibility. Thanks for the info. Wow.
Nobade
04-24-2014
Varying the pressure won't change the speed, but it will change the density. Since I use my powder in cartridges I want it as heavy as possible, so I do pull-ups on the press's jack handle and get as much pressure as I can manage. Leave it for 5 minutes and the puck is ready to dry for a couple of weeks.
Texantothecore
04-29-2014
I will probably be doing some testing of various formulations as well as with various densities using a chronograph for the testing as the flexibilty of the powder is just amazing.
A few months ago I loaded up my 45-70 with 70 grains of ffg with a roundball on top. At 300 yards the spray of wet berm dirt into the air was quite impressive and I am looking forward to seeing what else can be done with it. On the basis of the amount of ft lbs observed at the berm face it appeared that it might be a legitimite deer load.
I have no idea what the speed of that roundball was but it was very quick, a big surprise.
Boz330
04-29-2014
For deer I think I would stay with a real boolit not a round ball. It has the ballistic coefficient of a sheep turd and not very heavy. Close up it might OK but I would be leery at 100yd with the fast twist of a 45-70 barrel. JMHO.
mold maker
05-01-2014
I finally got a really fast burning BP. Instead of the usual POOOOF, this just flashed. (1/4 tsp in <1/10 sec.) This time I taken lots of extra time milling separate and then the mix. It is extremely fine milled and burned really clean.
Now a new question. Will compressing it into pucks and crushing to useable powder grain size, slow it down to a more usable burn rate?
I can't see a case full of this stuff being safe.
Texantothecore
05-01-2014
It will change the burn characteristics. After you have compressed and corned we'd be curious about what happens with this batch.
I'm quite curious to hear what happens as my current batch is like yours, everything finely milled before the incorporation run, because on my first batch I got too excited and didn't fine mill all the components first. I thought the potassium nitrate was well ground out of the bottle but it was not. The kno3 and the sulfur have been reduced to airfloat and it is quite impressive.
Boz330
05-02-2014
From day 1 I milled everything together. My CC was just run through an old meat grinder so wasn't anything close to air float. I tried several times to just screen it and load in a cartridge and had velocities in the 1000fps range. When I started corning the velocity went up to 1200-1250fps range. My competition load with the same boolit and Swiss is 1275fps.
I compress my pucks in a vice so the consistency isn't what it would be in a hydraulic press and I'm sure that makes a difference beyond 125yd which is all I figure on for hunting. I found that 3F worked best for me as far as accuracy, YMMV.
I think you guys might be over thinking this, load some up and run it across a chrono and see what you get, you might be surprised. The proof is in the pudding so to speak. My system is about as simple as it gets and has put meat on the table twice and provided some fun in competition at 300yd. I wasn't expecting much in the way of hits but the powder performed way better than expected. At 500yd the wheels fell off though, but I didn't make it for competition. That is where being anal retentive might prove to be the way to go.
Texantothecore
05-02-2014
Would it be possible to mill or cut two slots in a deep socket to accomodate the handle on your vice? You might be able to use a torque wrench to generate consistent pressures on your vice from batch to batch.
Boz330
05-02-2014
Quote Originally Posted by Texantothecore
Would it be possible to mill or cut two slots in a deep socket to
accomodate the handle on your vice? You might be able to use a torque wrench
to generate consistent pressures on your vice from batch to batch.
I believe that I am probably tightening beyond what my torque wrench would do. I'm not all that unhappy with the results I'm getting now for what I'm doing with it. A hydraulic press is in the cards somewhere down the road when I get around to it. Just need to be in Harbor Freight at the same time as the money in my pocket.
Eagle66
06-08-2014
Read the whole thread and now I'm more confused than ever. Short & sweet; I got the HF press, gauge, etc. Compressed my meal @ ~1450 psi. After drying, the density was ~ 2.2 g/cc, somewhat over the commercial number. Planning to chrono it, of course, but I'm concerned that this density may be too much for proper function. Too much bang, maybe? Maybe I should reprocess it with less squeeze? Just shoot it, but make sure my measures account for the higher density?
Boz330
06-09-2014
Just shoot it. Some commercial powders are denser than others. Swiss for instance is 10+% heavier than Goex.
The only place that you get into trouble is trying to compress too much fine grained powder in a case. If you weigh your charges you should be fine and if it is too dense just add wads to make up the difference and work up.
Texantothecore
06-11-2014
Quote Originally Posted by Boz330
Some commercial powders are denser than others. Swiss for instance is 10+%
heavier than Goex.
It would be instructive if our users weighed a cc of Swiss and Goex and posted the weights here. It didn't occur to me that densities would be different but it could have a substantial effect on velocity.
Castloader
06-23-2014
Hey guys, newbie here. I'm assuming that the ultra fine powder that gets generated during corning could probably just be re-pressed with a little water and re-corned, correct? I made a couple small batches and unfortunately about 60% of the powder went through the 50 mesh screen. I have screens all the way up to 400 for other purposes, I'm learning that for BP, they aren't very useful.
Boz330
06-23-2014
That is what I do, minus a little for flintlock prime. You do get a lot of fines. My best results have been from 3F which stays on my 30 mesh screen. Bigger is reground and smaller is re-corned.
Texantothecore
09-29-2014
That is exactly how it is done. Just wet it and press and you will get 100% utilization of your green meal.
Texantothecore
10-31-2014
Shop tip with the 12 ton press:I picked up a 2 ton hydraulic jack, put in the press frame and now use it as a vise. Best vise I have ever had. The orientation is different but it does not require a heavy table for mounting the vise.Try it, you'll like it.
cal50
11-02-2014
Making good powder is fun and addicting...
p