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View Full Version : Cylinder rubbing on barrel, part way around



fatelk
09-01-2021, 03:49 AM
I've got this neat little revolver that I bought a few months ago. It's an old S&W Regulation Police in .32 S&W Long. It's a slender little 4" barrel I-frame, made sometime in the 1930's as near as I can tell.

It's in great condition, looks mechanically perfect and the finish looks excellent except for a blotchy spot on the frame, no big deal. I didn't measure the cylinder gap because eyeballing it, it looked to be just right. When shooting it, I noticed the occasional hitch in the double-action pull. I soon realized that it was only on a couple chambers. At home I checked it over carefully and see that sure enough, two chambers on one side of the cylinder rub very slightly on the barrel. Very odd. I couldn't see any sign of damage, or anything bent in any way.

I then got out my calipers and carefully measured the cylinder overall length at each chamber. Sure enough, the cylinder is .002" longer on that side. Has anyone seen this sort of thing before? It sure looks like it was made that way, because this little gun doesn't look like it's ever been fired much at all. End-shake is very minimal. I haven't checked to see if a K-frame bearing shim will fit this gun, but even if it would, it would have to be a very thin one. I suppose the best thing would be to have a gunsmith chuck the cylinder up on a lathe and carefully true it up.

Any of you revolver-smiths worked on this sort of thing before?

Mk42gunner
09-01-2021, 07:31 AM
I never noticed that before, but it could be fairly common.

The shims sold for a K frame will not fit your little I frame. I base this on the fact that there are different sized alignment gauges for the J, K, and N frame S&W revolvers. IIRC the L frame uses the same guage as the K, but don't quote me on that.

If they sell shims for a J frame, they may possibly work for the I frame.

I'm not sure, I was taught the peen and file method of curing endshake for duty guns so I have never installed any shims. (Under the theory that more parts means more things to go wrong at the worst possible time).

Robert

country gent
09-01-2021, 07:43 AM
Any machining done will also destroy the finish on a blued model it can be touched up but nickel or other plating's will be much harder to work and touch up. If the gun is shooting good I would really consider leaving as is as an value from age will be lowered with the changes.
Since you know where the high spot is a few passes with a fine stone over that area with light oil will remove the high spot and bring it down to the rest of the cylinder. Work slow and easy with a new fresh stone oil, check and measure often.

KCSO
09-01-2021, 09:45 AM
You first need to figure out HOW that cyliner got cocked and fix that first. They don't come that way and I would guess that the crane might be a little bent. Make sure everything is plumb straight first. then true it up in a lathe if necessary.

TNsailorman
09-01-2021, 10:04 AM
Yes, I bought a 1989 .45 revolver from S&W on a special run. The first competition I shot it in, it did well on the first set of targets but froze solid(cylinder would turn in double action) on the second set. After I had to withdraw from the match, I called S&W and talked to a young lady who would only say that they would not repair it free of charge and that I could send it in and they would inspect it($15.00 charge) and repair it(at my cost). I sold the revolver at a $125.00 loss to a local gunsmith. He later told me the cylinder was not machine square on its face. He said he machined it square and it shot like a dream after that. It was many years before I bought another new S&W of any kind. That was the first and only S&W revolver I ever found fault with and I have owned more than a few. It left a bad taste in my mouth for S&W's for a while though. my experience anyway, james

243winxb
09-01-2021, 10:30 AM
Have a gunsmith chuck the cylinder up on a lathe and carefully true it up.

I had to do this to a 22lr , S&W, new from the factory back in the 70's

rockrat
09-01-2021, 10:46 AM
I was at an IHMSA shoot one time and was at the DW table. Fellow there had one of the stainless super mags he was working on. Cylinder was dragging and the factory rep. took a fine file and worked on the front of the cylinder with it. Inspected his work, checked cylinder gap, file again, inspected his work then chamfer tool on cylinder mouths and pronounced it was fixed!! Fellow shot it later that day and it worked fine.

Char-Gar
09-01-2021, 11:32 AM
Consider the possibility that the barrel root is not square. That is not uncommon.

FLINTNFIRE
09-01-2021, 11:59 AM
It drags on 2 cylinders and is longer on that side , true the cylinder up it is not the barrel .

Had a 27 that they sent out with no cylinder gap , quality control was lacking for sure .

DougGuy
09-01-2021, 01:11 PM
LOL make it a 4 shooter! It's CHEAPER!! :kidding:

fatelk
09-01-2021, 01:33 PM
Thanks everyone. I think I will very carefully touch up the high spots with a stone. It shouldn't take much. I was worried that something was bent at first, until I measured the cylinder. I assume that whoever originally machined the cylinder face, back in 1935, was a little sloppy in their setup. This revolver is in beautiful shape except for a couple blotches on the finish, and some odd cosmetic dents on the top of the top strap. Even the grips are beautiful, with a patent date of 1917 stamped into the wood on the bottom. I'd never seen that before, but I looked online and see that that's common to this model. I only paid $400 for it; I think I got a really good price.

fatelk
09-01-2021, 05:12 PM
I took the cylinder off and all apart. I cleaned and blackened the cylinder face, put it back on and turned it a few times. Here you can see where it's rubbing.

288189

The confusing thing is that I re-measured the cylinder length, carefully at the edges where it's actually rubbing, and found I was wrong before and the length is actually consistent all around. So maybe something is bent slightly after all, not sure.

So here's what I did: I dug out my Power Custom cylinder bearings and measured one. The ones I have are for K-frames, and were about .005" too large in diameter to fit. I suppose I should order some J-frame bearings, but for now I used a diamond hone to carefully reduce the OD to where it fit. I put a .002" thick bearing in the gun and it has absolutely no end shake at all now, but the cylinder doesn't rub!

I realize that this probably isn't the precisely correct way to fix this, but it seems to work, and I'm good with it. Any thoughts?

Tar Heel
09-01-2021, 05:19 PM
I find myself wondering if the ratchet is not the problem. If it has too much meat on it behind these chambers, the hand is pushing the cylinder too far forward.

fatelk
09-01-2021, 05:22 PM
Here's the petite little gun next to a slightly larger one for contrast.

I'm enjoying loading and shooting the little .32 S&W Long round. I picked up a gallon bag full of 1x .32 long brass a few years ago at a gun show for cheap, finally get to use them now. :)

288194

fatelk
09-01-2021, 05:25 PM
I find myself wondering if the ratchet is not the problem. If it has too much meat on it behind these chambers, the hand is pushing the cylinder too far forward.

Interesting thought. That would tend to tilt the cylinder slightly, rubbing on that top edge, wouldn't it? I hadn't thought of that.

Either way, it seems to rotate consistently and easily now. I'll take it to the range and see how it shoots next time I get a chance.

stubshaft
09-01-2021, 06:13 PM
I was at an IHMSA shoot one time and was at the DW table. Fellow there had one of the stainless super mags he was working on. Cylinder was dragging and the factory rep. took a fine file and worked on the front of the cylinder with it. Inspected his work, checked cylinder gap, file again, inspected his work then chamfer tool on cylinder mouths and pronounced it was fixed!! Fellow shot it later that day and it worked fine.

I had one of the first DW 445 SM produced. The serial number was two digits and the brass wasn't even available for it yet (I had to fireform and shorten 348 Win. brass). It went back to the factory three times because the cylinder wasn't square to the center pin. It is not as rare as you would think.

fatelk
09-03-2021, 04:04 AM
Very interesting. I took this little gun out to the range again today, and my simple fix seemed to have an effect on accuracy.

I wasn't terribly impressed with accuracy after I first bought it. My previous attempts resulted in around 4-5" groups at 25 yards. Today I mostly shot some cans, but shot two careful 6-shot groups from the bench at 25 yards. One group was about 2.5", and the other was 5 rounds inside 1.5" with a single flyer making it about 3". That's really about the limits of my abilities, especially with such a tiny grip and primitive sights. It shoots a few inches left at that range, not sure much can be done about that, what with the fixed sights.

Tar Heel
09-03-2021, 05:23 AM
Very interesting. I took this little gun out to the range again today, and my simple fix seemed to have an effect on accuracy.

Nice to hear you got her shooting better. The little 32's are a delight to load for and shoot.

5614estell
09-03-2021, 07:51 AM
It seems like a lot of fixed sight revolvers shoot to the left. Wrap your finger around the trigger further. This will cause you to pull the gun to the right.