Thread: .45-70 powder compression confusion
Retrieved: 10/17/2014
Last Post: 05/13/2009

I've been loading .45-70 black powder in a Sharps for a month or two and have read a good deal about it. However, I'm confused about something. I'm using 65 grs. (volume) of Goex FFF, a .03 over powder wad and a 405 gr. Lead Flat Nose bullet. Many of the comments I've read about loading seem to recommend compressing the powder around 1/16 to 1/8 inch. Using a 24" drop tube my 65 grains come to within 1/4' of the top of the case (give or take a mm) With my 1.02" bullet loaded to the crimp groove (2.52" OAL) and wad, that gives me an actual powder compression of .38". Now I've shot quite a few of these and they perform very well. But if I want to load the classic 70 grs, that's going to give me even more compression. Am I missing something?

ribbonstone
03-28-2009

The classic 70gr. was loaded in thinner, "balloon head" type cases. Really isn't easy to get more than 65 gr. of powder in a modern case and have the bullet seat very deeply. For most single shot shooters, seating depth isn't a real issue (so long as it doesn't fall apart in your hands, we kind of "baby" them on their trip to the chamber), so some people have fit 70gr. with shallow seating using various compression techniques. I'm really not fond of mechanical compression dies and don't like to use a soft bullet for that kind of compression force.

But if 65 is doing well for you, then keep doing what you're doing and ignore other advice... personally, 65 seems just about right to me.

CoyoteJoe
03-31-2009

I'd suggest you pull a bullet from one of your loaded rounds, dump the powder and examine it. I think you may find that you are crushing quite a bit of powder to dust. In a single shot rifle there is really no need to seat the bullet to the crimp groove. I'd locate the OAL which just kisses the lands and go from there.

Pete D.
04-02-2009

That five grain difference is just not worth the trouble.

John Kort
04-15-2009

The early .45-70 cases that were of Solid Head Button Pocket construction (balloon head) held 3 grs. more b.p. than modern cases according to tests I have run.

Also, densities of different b.p.'s can vary. For instance, Swiss is about 10% more dense than Goex... at least the lots I have are. In otherwords, 70 grs. of Swiss will occupy the same volume as 63 grs. of Goex (my lots).

Voyageur
04-15-2009

With the .45-70 Govt. the problem of reduced case capacity can be circumvented by the use of a duplex load to maintain the velocity. I have described the process in a previous thread.

The difference in balloon and solid head cases can be seen below by following the link to where I put up cutaways for demonstration to folks.

Yellowhouse
04-19-2009

Although 3f can be used, you may want to try 2f and 1f. I really believe that is way too much compression for 3f. No more than half that would be more desirable... or none at all. Goex 1f can take that type of compression easily and seems to require it while the more dense Swiss tends to not like any or very little compression. For certain, I think that kind of compression with 3f is counterproductive and you are very likely really crushing your powder column.

Try coarser granulations. You may find an increase in accuracy at longer ranges and that it is a lot easier on your shoulder.

El Tigre
05-08-2009

Black Powder needs no compression. Some of them do not like it. By using a drop tupe compression is not needed and if you have a single shot as a Sharps it is more important to bring the bullet near to the lands as CoyoteJoe explains.

I am useing Schweizer 5 in my 45-120 Sharps. Schweizer 4 in the 45-70 Sharps.

In June, I hope, I will have my new Spencer and I will load the 56-50 with Schweizer 1 or 2.

Late this year I will have my 54-110 Sharps, build by a friend of mine, a really nice Sharps with a powerful caliber. I will also use Schweizer 5.

The issue is that Schweizer powder does not like any compression. I fit the bullet by hand in the brass, no crimp at all and the brass is not re-sized. I use it as it come out of the Sharps after shooting.

mcg6637
05-09-2009

Because of all the great replies, since originally posting my question I have experimented with 60-65 grs. of Goex and Pyrodex in various "f's" and various compressions. Frankly all results have been acceptable for my use and ability. But some have been easier than others, both in loading and on the shoulder. So I'd just like to thank everybody for the help. This is where these forums reallly shine!

R.Clem
05-12-2009

Try trickling the powder into the drop tube slower.

What you are getting for uncompressed depth to the top of the wad with 65gr FFFg, I am getting with Goex Cartridge and Graf FFg.

I compress these down another .30 inches to seat a long Postell bullet.

msdh
05-13-2009

You did not state what brass you are using. And believe it or not the capacities of different makes is not at all consistent. When I used to load for my Shiloh I used Winchester brass that is noted for holding a little more than most brass. I could routinely fill the case with 70-72 grains of Goex Cartridge and fit a Lyman Postell on top with a .030 wad. I used a 28 inch drop tube and poured slow. My compression was about .320-.340 of an inch. I used a compression die not the bullet to compress the powder. A lot of very good info can be read on the Shiloh forums.