Little tricky things that I've picked up along the way.
You've installed a shock buffer for frame protection on the range, (I don't recommend using them in a carry gun) and you've got short-cycle malfunctions related to reduced slide travel. You really want to use a buffer, but the number of malfunctions are getting on your nerves...
Get a full-length guide rod and chuck it up in a lathe. Face off the head from the backside to about .045 thickness. Face off the same amount from the butt-end of the rod. Use a Hiett .090 shock buff. The combination will return about a 32nd of an inch of the lost slide travel. Doesn't work every time, but it will for 9 out of 10 pistols. Any machine shop can handle the job in 5 minutes.
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You've got a pretty good fit on the barrel, and the bushing is a good fit in the slide, but the groups are stringing diagonally, and they could be a little tighter. Could be a some rotation of the barrel (torquing) due to the way the lower lugs are effecting the lockup.
First, check to make sure that the link isn't locking the barrel into the slide. If it is, get a slightly shorter link. Check to see that the slidestop pin is supporting the lower lug evenly from side to side. Color the bottom of the lug with layout fluid or a blue felt-tip marker. A chisel point marker works best. With the link removed, hand-cycle the gun a few times and disassemble. If the dye isn't worn off both sides evenly, the lug isn't properly supported by the pin.
Get a 6-inch length of quarter-inch cold rolled round stock and turn, file, and sand with emery cloth (lathe operation) down to .195-.196 diameter. Get some fine lapping compound...600-grit garnet lap will do...Put a little on the bottom of the lower lug, and assemble the gun, using the turned rod in place of the slidestop. Using an old recoil spring that has been cut 4 coils shorter than original, let the slide go to battery and turn the rod a few times. A cordless drill on low speed can be used, but be careful.
Put a little light downward pressure on the barrel hood and goose the trigger on the drill a couple of times. Take the gun apart and recheck to fit with more layout fluid. When you get even dye removal on both sides of the lug, you're done. Rinse off all traces of the lap, and apply a little straight J&B Bore Cleaner to the lug and slidestop pin. Shoot the gun about fifty times and remove the bore cleaner. Your groups should improve.
Go slow with this. The objective is to remove metal only from the high spot on the lug, and no more than necessary to get even support. The weakened recoil spring is to prevent reducing the thickness of the feet, or moving the slidestop pin farther back into the feet. If you have access to a 10-pound spring, so much the better. This also helps to eliminate any problem with ths slidestop popping out during the cycle. When the lug is high on the right side, it tends to push the pin to the left. Kill two birds with one dab of lap, so to speak.
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Got a little stem bind causing a slight hang-up in returning the slide to battery?
Look at the link in the linkdown position. If the link is the right length in vertical lockup, but the barrel is riding it as it goes around the front of the lower lug, go to Lowes in the Dremel section. Get a set of the little round, blue chain-saw sharpering stones. (3-4 bucks for a pair) The stones are about .200 diameter. Use them in a Dremel to elongate the link's slidestop pin hole on the end near the smaller hole by .3-4 thousandths. You'll have to follow the radius with a slight rocking motion. Be careful to keep the stone square with the hole. This will slow the barrel rise when the bullet nose hits the throat, and keep it farther down in the bed of the frame for a little longer and eliminate most or all of the stem bind. Don't remove any material from the bottom of the hole. This is the area that the pin uses to unlock the barrel, and elongating it there will delay linkdown timing. This is an expedient method, and will work well. The best way, however, is to get a slightly shorter link. This will make it necessary to measure the link across pins to find out exactly what the center-to-center hole spacing is, and ordering a link that is .003-.005 inch shorter. "Standard" link spacing is .278 inch. Wilson # 1 is .273...#2 is .275...and #3 is .278
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Plunger tube loose, and you don't have a staking tool? (or even if you do)
Remove it and rough up the mating surface with some coarse paper. Scratch the mating surface on the frame where it won't show. Degrease it thoroughly and use a little J B Weld on the surfaces and on the legs. Install the tube, making sure that it's oriented correctly, and LIGHTLY clamp it in a bench vise. Wipe off any excess that squeezes out. Let it cure for 24 hours. A new plunger tube makes for a stronger joint, but the original will do fine if the surface is prepped well. I've installed plunger tubes like this, and haven't had a problem with them in years of use.To remove the tube later, heat it just a little with a propane torch...just barely uncomfortable to the touch. Use a drift and a 4-ounce hammer to bump the tube on the bottom and top along the length. It should pop free with a few taps. Worry it the rest of the way off with a small knife blade by going back and forth on the ends.
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Slidestop binding on the edges of the slide as it tries to engage?
Get a small, triangular file and make a few light strokes in the top of the slot to bevel it will usually reduce the binding and allow the stop to move upward smoothly. Bias the cutting pressure to the outside so that the stop won't try to walk out of the frame. This is trial and error, and should be done carefully. One stroke and check...Repeat. If it's still binding deeper in the slot, use a flat file to remove just a tiny bit from the outer wall in the slot. (left side) Again...take the cuts on the side that won't let the slidestop "walk".
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Rear sight loose in its dovetail?
Drift the sight out, and get a prick punch and a small hammer. Use the punch at an angle to kick up several tiny burrs in the bottom of the dovetail. Go in both directions, starting at the outer edge and working your way in. Several small burrs are better than a few large ones. Reinstall the sight and return it to zero. Unless you drift the sight a lot, this will last for a long time.
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Need a recoil spring plug for a Commander, and all you have is a spare for a 5-inch gun?
Chuck the long plug up in a lathe and face it off to length. Deburr the edge with a smooth mill file. Works fine. Works for the barrel bushing too, but you'll need to mount it on a mandrel. Machine shop job...5 minutes, tops. Chuck lightly on the plug. They're pretty easy to crush.
2-piece guide rod giving you fits? Turn it into a one-piece.
Take it apart and degrease the threads. Apply 24-hour epoxy or good old J B Weld, and screw it together tightly. Allow to cure for 24 hours. Chuck the rod in a lathe and face off .135 from the end. Check the fit to make sure that the bushing will swing past it. Adjust as necessary. Remember to bevel the end with a file while it's in the lathe. Most work with about .150-.155 off the end in case the machine shop doesn't want the gun there for final fit.
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Files clogging up and "pinning"? (cutting little gouges in the workpiece)
Use a file card to remove the clogged chips and fill the teeth with plain chalk. Repeat as necessary. NEVER oil a file or use aerosol solvents to clean it. A very good scrape can be made from an old triangular file. Lay each side flat on a belt sander to remove the cutting teeth and leave knife edges. Be careful to not allow the file to overheat. When it starts to get hot to the touch, lift it and let it cool. If it overheats, the temper will be destroyed. Quenching it in cold water will preserve the temper. Resharpen as necessary. When filing flat surfaces that need to be kept flat, it's better to lay the file on the bench and draw the workpiece along the length. Turn the file so that you will need to draw toward you to make the cut. Draw straight back with even pressure, stop, and lift the piece straight up. Never use a file in both directions. Certain Swiss-pattern files will cut in both directions, but unless you're sure of the design, be safe and cut unidirectionally.
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Getting hit in the face with hot brass?
Most extractor hooks are square on the bottom corner. Use a medium India stone to radius that corner a little by swiping the hook on the stone with a rocking motion. This will let the case twist off the extractor at a slightly different point, and kick it out at more of an angle. It also works to relieve any contact with the case as the round climbs the hill to enter the chamber. If you have lazy return to battery, and notice gouge marks in the extractor groove, look to that corner.
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Follower riding over the slidestop lug and tying the magazine up in the gun? (Remove magazine by popping the slidestop out slightly instead of ripping the magazine out. This can be done easily without disassembling the gun. A little practice will get the whole procedure down to 3-5 seconds)
Remove the follower and turn it facing you. Grasp the top with a wide pair of pliers as close to the shelf as you can.(in your left hand) With your right hand, wedge a flat screwdriver between the top of the follower and the shelf and pry it outward LIGHTLY just a bit. This moves the elevator shelf farther into engagement and puts a slight upward angle to the outside. This forms a better captive angle so that upward pressure from the magazine spring draws the shelf toward the lug instead of pushing it away. Careful now. The shelf will snap off easily if too much force is used. It only takes a little.
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Plunger assembly flies out when the thumb safety is removed?
Remove the assembly and take the pins out of the spring. Use two small nails in the ends of the spring and pull in opposite directions to stretch the spring a bit in the center.Recoil spring plug getting loose from the spring on disassembly? Heat about a quarter inch from the front of the open end of the spring, and put a slight outward kink there. If done right, it will make a friction fit between the end of the spring and the plug. When time comes to remove the plug, pull and twist it off.
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Nose-diving top round from slidelock? Remove the follower and spring, and use needle-nosed pliers to put a slight upward bend in the top coil. Don't bend from the turn, but on the straight part. This gets a little extra upward tension on the front of the follower to help keep the round moving in a straighter line. Never stretch a spring to get more tension. Stretching a spring exceeds the elastic limit and will work for a very short time.When the stretched part collapses, the spring will be weaker than before the stretch.
Files:
Beeswax is handy. If a new file wants to "chatter" (not smooth, wants to grab) apply small amount of beewax, will smooth, not affect the ability to file, aids in preventing rust on file, and beeswax is easy to remove from file itself and pc being worked on.
Beeswax is also used in same manner for small saw blades and gravers... though oil of wintergreen I prefer for gravers.
I thought I was the only person to use chalk on files. Get indegestion while working on gun.
Beeswax!
Yes! Beeswax is good. I HATE that screeeetch...
While you're at the machine shop, have one of the machinists demonstrate how to follow a radius with a file. It's easy to do and a handy little skill to have in your growing bag-o-tricks.
Also, whenever you have a flat surface that's too large to pull on the file, or two parallel surfaces that you have to file evenly, lay the file sideways and use your fingertips to keep it flat as you draw the file toward you. It's called... Draw Filing!
This works well on the flats of slides that need to be cleaned up before finishing. Really makes'em flat and true. Especially useful after somebody has polished one with a Dremel and a buffing head. It gets the waves out.
(Speaking of Dremels..)
Every once in awhile I polish the trigger stirrup and disconnector on my GM. I have been using that jewelers red rouge on low speed with a felt wheel but when I was in Lowes picking up some more cut off wheels for it (for work) the older guy I talked to said the green rouge is good also and I bought some of it. I havent used it yet but was curious about the difference in the red & green. Which one's more abrasive? Should I be using one over the other? The red gives me a mirror finish but the green says it will also and I'm just a wee bit hesitant to use it before I understand the difference in them.
What do you use for polishing?
Unwritten rule:
One must keep a file that screeches handy. Sometimes you do not need /want the boss, to look over your shoulder... works on Mother-in-laws I found out once as well.
I also will use a smooth flat surface and lay the file on it and holding the pc working on use the file that way.
More important to use a smooth flat surface (pane of glass, plexiglass, countertop...) when using sandpaper. For example, say you need to sand a disc, sandpaper on flat smooth surface, and sand disc using just enough pressure with fingers (let the tool do the work). Change grit as need. If a polish is needed, Chamois with Fabulustre ( arious rouges work as well, just Fabulstre is easier to clean up) stretched onto a pc of 2x6 (flat and smooth of course) works.
Emery sticks:
Lessee, old yard sticks (used up worn emery sticks) ,emery paper /sandpaper of designed grit. Lay 'stick" onto paper, lightly scribe edges ( keeps edges sharp and crisp) and "fold" to desired thickeness. Scribe before each "fold".I use staples at top and bottom o both sides. When a side gets worn... just peel away exposing a fresh pc of emery as need.
Chamois (the real deal not synthetic) stretched onto a "stick" is really handy. One can actually high polish without ever having to use a Foredom Flexshaft or Dremel tool.
I did a lot of hand finishing. Sometimes a Power-Driven tool just gets one into trouble quicker.
Rouges:
Been awhile... but basic the Red was designed for yellow gold ( 10 -14k). Green, Yellow, White, better used for 18 -24 k golds, some yellow, some white, and platinum applications.
Rouges by nature are hard to clean, old time jewlery and watch shops had RED Rouge all over the place. That dust went everwhere, attached itself to everything and was a pain in the butt to remove.. and then not all was removed. Ruins clothes.
Fabulstre (tm) came out IIRC late 60's. Happy Day! Polished a variety metals, better, easier to clean, less mess in shop (suspect less toxic in breathing dusts from rouges) more cost effective, (one product replaced 3 or so).
One of the few times something new actually did what touted. Oh we kept the rouges around, still had/have a place... just not needed near as often.
Oh that little buffing wheel or pc of Chamois with Simichrome by Happich... try that instead of rouge. IME/IMO... Simichrome worked better for me than Flitz... then again I might be biased...I don't recall seeing Flitz in late 50's... I think I was born with a tube of Simichrome in '55... I just grew up always seeing a tube around...
Polishing
Easy to see that my main man sm knows his way around a machine shop...
Edward, I don't use any of the rouges except on a Dremel buffing wheel to polish concave surfaces. Throat, ramp, etc. For flat surfaces, such as your trigger bow, I lay it flat on a piece of 800 grit wet or dry paper glued to a piece of glass. When I get it prepped, I get an old piece of denim and work some J & B Bore cleaner into the fabric, glued to the glass and use that for a final polish. I also use silocone compound as glue so it will come off the glass easy. Glue just around the edges/sides to keep the working surface flat..
Another one!
Got a barrel bushing that could be a wee bit tighter in the slide?
Lay the bushing face down on a concrete floor. Get a ball-peen hammer and put the ball end in the rear of the bushing...the part that goes into the slide. Hit the flat face of the ball peen hammer with another hammer... not too hard now... just rap on it semi-firmly. Check the fit after every rap. You'll wonder where the "rock" went.
TIP:
Got an old pistol with a little too much up and down motion in the trigger and ya don't wanna use an aftermarket?
Find a piece of flat stock that you can slip the bow over and lay it on a solid surface, like the tailpiece of a heavy bench vise. Use a flat-faced punch to go along the top and bottom edges (sides) with a hammer and displace some metal to make the bow "taller". About 5-6 places on both edges top and bottom oughta do it. File/stone the bow to fit in the trigger channel in the usual way.
Edward said:
I used to use Simichrome on my trigger until I got my dremel and the rouge
makes it a lot faster than doing it by hand. Is this a bad idea? I don't think
I've been removing metal but from how you guys sound maybe I should go back to
doing it by hand again...
The problem with using a Dremel to polish a flat surface is that it's easy to create a dip wherever the buffing head stops. Different pressure will do the same thing as you pass it back and forth. I've seen several slides that look good after Dremel polishing... until the bluing is done. Holding the slide sideways under a light and peering down the length shows the wavy pattern.
Polishing on a hard, flat surface tends to hit the high spots, and make the surface straight and flat. It won't likely hurt anything on a trigger bow as long as fairly even, light pressure is applied and the you keep the buffer moving. As to getting it done faster with jeweler's rouge... The faster the abrasive works, the less margin for error. Since it cuts faster, it can ruin a part quicker.
I've put the final polish on trigger bows with a Dremel and jewelers rouge. To keep things straight, I use very light pressure and start off the end, make a one-way pass, and bring it off the other end instead of passing it back and forth along the length. Keep in mind that when you stop... you cut deeper into the surface. A micron isn't much, but 10 passes makes it 10 times as deep, and so on.
Careful with that Dremel.
EDITED TO ADD:
Edward said:
Every once in awhile I polish the trigger stirrup and disconnector on my
GM.
The flat face of the disconnector is best polished with a piece of 600, then 800-grit wet or dry paper on a flat hard surface. Use a little honing oil, and move the part back and forth (sideways) until the high spots are buffed well. With some disconnectors, you can't get a perfectly flat, polished surface without removing too much material. Then, go to the 800 grit paper and move the part in a figure 8 pattern lightly. Break any sharp edges by holding the part at a 45 degree angle and making a couple of light swipes. Buff the face on denim with J&B Bore Cleaner, and give the edges a litle attention again.
Rouge is an abrasive and removes metal. A dremel makes it work faster. What I can't understand is why would you polish a trigger and disconnector more than once? It sounded like you take them out once in a while and run them over a buffing wheel?
I added a little to the tail-end of the last reply on polishing the disconnector face. Works purty good, too.
How many of us have a pistol that has some slop in the hammer when it's down? This due to either the mainspring housing being mislocated, or the mainspring cap or the retaining pin is out of spec. Easy fix.
Remove the cap and chuck it up in a lathe. Face off about .010-.012 inch from the top to let it sit higher in the housing. Only rarely will you need to remove as much as .015 inch... about a 64th. This gets the hammer all the way atainst the firing pin stop. Any machine shop can handle it in about 2-3 minutes. Be sure to bevel the sharp edge with a file.
It can be done on a file, but you have to be very careful to keep the cut flat. Lay a smooth mill file on the bench, and draw the part across it smoothly with light, even pressure. Use emery cloth to smooth the sharp edge, inside and out.
Great thread, I've used red loc-tite on 'wiggly' plunger tubes.
Quote:
It sounded like you take them out once in a while and run them over a
buffing wheel?
That's what I do most of the time just plain cloth wheel. Sometimes I use rouge to bring it back to a mirror finish real quick.
As someone once told me, "haste makes waste." These days all kinds of operations are done with powered hand tools and it shows. If you inspect an earlier Colt you will find the radius are true (like the top of the slide) and at the back the frame matches the slide perfectly when the gun is in battery. This is because the polishing was done using contoured wheels that were shaped to fit the particular surface being finished. The only way to match this kind of work is hand polishing using a backer that fits the surface.
To polish the flats on a slide, glue a piece of emery paper of whatever grade you want too use on a board. Nail a strip of wood at one end that will stop the forward stroke before you get to the serrations. This way you don’t end up flattening them. Lay the board on the bench top and go to work. It will take time, but you won’t end up with waves.
As an aside: If you ever inspect a mint or like-new Colt Government Model National Match pistol made around 1935 to 1941 you will see what polishing and metal finishing REALLY is.
Amen Fuff! Wish some of the younger guys could see what Colt and Smith & Wesson used to be capable of. They had honest-to-God craftsmen on the job, trained and supervised by honest-to-God Master gunsmiths and armorers.
Another little trick here...
Sometimes we find that a chamber shoulder is a bit sharp, and accumulates carbon fouling. When this happens, it can screw up the headspacing and cause failures to return to battery. Even if it doesn't cause functioning problems, the more anal retentive among us likes to have the chamber area CLEAN, and sometimes it takes a while to get it all with a bronze brush and solvent.
Get a fired .45 Colt case and lay it on a bastard cut mill file mouth down. Use a 4-ounce hammer to tap on the rim wile lifting and turning the case to establish some "cutting" teeth in the mouth of the case. Run it over the expander ball in the die set that you've set the ball deep enough into the case to bell it a little. Keep increasing the belling intil you get a light interference fit between the case and the chamber wall. When it's just barely finger-tight, you can push the case to the shoulder and turn it while pushing lightly. The rough edge on the case mouth cuts through the carbon and leaves the shouder clean. It also cuts heavy carbon fouling out of the whole chamber. Follow up with a brush and solvent.
Loose grips: take blue painters tape, cut off a small strip and wrap around the gripscrew bushings. the grip should slide around no longer. Note, regular masking tape breaks down too fast from gun oils/solvents.
White dot sights: the paint getting dingy on your three dot sights? Apply a fresh coat and let cure... then seal with super glue. They will be more resilient to solvents.
Ambi-removal blues: hate removing ambi safties? Take the right side lever and cut a small notch above and slightly forward of the cross pin location. Make the notch just big enough so you can slip a pocket screwdriver in and to pry it out. When complete the slot will only be barely noticeable.
Grip bushing stuck on grip: you can do this the hard way... pliers... or the neat way.....clean the bushing and frame with alcohol then put a dab of red loc-tite on the bushing threads. Tighten the grip back down on the gun, let sit overnight and slowly/carefully unscrew the grip screw... waalaa!
Jeff... Now that you mention the loose grips... I've used little bitty rubber O-rings under the screw heads. Works purty good. Forgot that one.
Cast lead shooter with the sewer pipe deposits on your barrel? Warm the barrel in the oven until it's a little uncomfortable to handle. Scrub the bore with a dry brush that's about a half-caliber oversized to score the lead. Scrub with a solvent soaked brush, allow it to "cook" for a few minutes... patch out and repeat. It comes out much easier.
I just last night discovered that a standard issue M-16 barrel wrench makes a pretty good tool for removing the mainspring. Just lay it flat on the table top / work bench. Turn the MSH upside down, and push it down over the center lug of the wrench. This compresses the mainspring just enough to let you pop out the retaining pin, and doesn't require a 3rd hand.
Kudos Archangel! I never tried that one, even though I've got a barrel wrench. Good to know.
Oil of Wintergreen is great for gravers.
A couple of drops on a cotton ball inside an small tin on your bench. This makes "cutting" easier. Slivers "give way" during the cut, dip the graver onto the cotton ball impregnated, cut again. Helps keeps those old carbon gravers sharp. I mean it REALLY makes cutting stuff easier.
Oil of Wintergreen is useful for other cutting applications as well. I have used it when I was out of Tap Magic (tm) when a tapping fluid was called for.
Re-cap the tin, since this stuff evaporates...
Reminded of this simply because I re-cut the threads on a screw and threaded a blank to make a screw... yep used the wintergreen.
Good tip from sm. I've used it on everything from end mills to drill bits and reamers, too. Cheaper than CoolTool and smells a helluva lot better than cutting oil.
Erasers
I can't believe we forgot to mention these. Stainless guns...
What carbon fouling? You mean here... rub eraser over carbon... blow residue... done.
Good you added the Wintergreen Steve... trouble is with the likes of me... been at stuff so long, ''routine'' useage of various materials seems so unremarkable... it's forgotten as being anything special.
Now the eraser... dang... I HAD forgotten that one completely!
"Hole shrinking"
Only done this a few times on a firearm...many times on other stuff...so listen to Tuner, Mr Kennan, Old Fuff, bigjim...anyone but me for experienced advice - please.
This may be dependent on the ability to refinish the metal...
To "shrink" a hole.
Auto -center punch and "punch" around next to the edge. [ Ker-chunk, Ker- chunk...Ker-chunk] . NOT into the hole...next to the holes outside diameter. Insert a flat point in the Auto-center punch and "ker-chunk" those little "impressions" until burnished smooth as can. Now you can use a broach to fit the pin as need. Inside a shotgun reciever I cold blued.
Variations:
I made my own punches to fit the auto center punches. I also had some smaller to "itty -bitty" auto center punches. Pointed, less pointed, rounded, flat, concave...in both steel and brass.
I did a lot of this with same /similar punches and used a variety of hammers... small chasing hammers if you will. tap-tap-tap-tap. Adjusted punches, hammers to task.
Me being me I am prone to start too light and ease up.
Maybe not for the 1911... maybe not most applicable to firearms per se'... handy just the same.
Basic principle is one is moving metal (working the metal) from the outside diameter area around the hole more towards the hole iteslf.
You do not "kick metal" into the hole... no density, no strength.
Measure the pin for instance and choose appropriate broach. If not used to using broaches... measure smaller than the pin and mark with tape, felt tip... for first timers use tape. One cannot slip and go too big.
Go slow and a snug fit can be obtained. Yes it will last.
If at all possible do this from inside. Example again... I did this from inside the receiver... exterior was protected by a pc of chamois, and balsa wood, finish was not disturbed.
Sure, the center punch deal will do good... all a case of upsetting the metal, to just gain that ''thou'' or so of reduction in I/D... this following can help too tho, with less marring...
Take a 60deg lathe center... if it's #2 morse that's a good size... and the tang can take a few blows from a copper hammer with no probs.
Rest this center in the hole to be ''treated'' .. and apply a few quite light taps... but, important to keep the center as square to hole as possible.
Check with pin at stages... until pin will just not quite enter. If then pin has the slightest of chamfers... it should be possible to drive it home with a brass hammer. Of course... the upset is only local to outer part of hole but... it is an easy fix for a pin that does not have to go in and out too much.
If the upsetting is overdone then a pass with a suitable reamer will help.
I like a "true'd up" impact surface on my guns. I'll turn the barrel upside down, wrap a piece of sandpaper around the hood and lap away any high spots so the barrel will seat down as flush as possible.
Last night I went to replace a dovetailed rear sight on a rifle and the new sight could be pushed all the way through the dovetail with finger pressure. I used your prick punch tip on the bottom surface and then tapped in the new sight nice and snug. If I hadn't read that tip a few days ago, I would still be in a bad mood. Thanks again.
Good post and absolutely correct that the barrel should center up with the firing pin hole. My point was to equalize the point of support between the lower lug and slidestop pin, which shouldn't be more than .003 inch difference between the height of the 2 sides of the lug. If the barrel isn't centered up, reducing the high lug to equal the low one likely won't make a whit of difference in the vertical. lockup, and will probably help the accuracy to some degree. The main benefit is to prevent overstressing one side of the lug while the other side loafs.
Again... we're talkin' field expedient repairs and adjustments on production guns...not buildin' match-grade pistols.
Surface rust on a blued gun? Get a piece of aliminum foil and wad it up. Soak it with oil and scrub the rust spot. It will take the surface rust off, but will not damage the finish as the finish has a higher tensile strength then the foil. Wipe aluminum residue off of gun, touch up with cold blueing if necessary, enjoy.