Cyl. gap for S&W Mod 51, 22 mag?

[shotgun-2]

I bought a real nice Mod 51 S&W, about 98%, maybe unfired.
PROBLEM-- Took gun out to try and after about 30-40 rounds fired cylinder was binding. Hard to rotate and would stick closed. Cleaned gun and can now close and rotate cylinder. It did not look extreamly dirty or leaded.
Cylinder gap is only about .002", that seams too tight to me, but I'm pretty sure that is the way S&W sent it out.
What is the fix? Can I try to stone the barrel or would this take a pro or the factory to fix?
There is no end shake and were no marks on the end of the barrel (forcing cone) or cylinder prior to shooting the gun, now there is a slight polished spot on the barrel.
It is clean under the extractor as well.
Anything I might be missing?

Thanks, Shotgun-2

 

[351 WINCHESTER]

Take some masking tape and wrap topstrap so it doesn't get scratched and just take off a little at a time taking care to keep it square. I don't like a gap under .004 or so just for the problem you are having. FYI a lot of revolvers forcing cones are not square so you may just have a high spot that needs to be removed. Just go slow and be careful.

 

[dfariswheel]

Problem is....there may be a different problem.

Among them is a sprung cylinder joke, to yoke end shake, not cylinder end shake, or another problem.

Before I started altering an expensive revolver in like new condition, I'd be making SURE what the actual problem is.
If it is simply a matter of too-close a barrel/cylinder gap, I certainly wouldn't be taking a stone or file to it.
Its near impossible to keep the barrel perfectly square and an uneven barrel will produce lesser accuracy.

I'm a retired Master watchmaker/gunsmith specializing in Colt revolvers. Of necessity and training, I was about as good with a file as its possible for a human to be, and I'd never dream of stoning or filing a barrel.

My advice: Take it to a pro pistolsmith, or send it in to S&W so a real expert can diagnose the real problem and correct it.
Its not real smart to buy an expensive and in demand revolver and then start hacking around on it in the hopes you fix a problem that you aren't even sure what it is.

 

[Ed Harris]

In the .22 WMR be sure to clean well under the extractor and its recess in the cylinder, as even a single particle of unburned powder there can back out the exrtractor star and bind up the gun. Be sure to elevate the muzzle when you eject the empties and carry a brush with you. That being checked, best way to correct a tight barrel-cylinder gap gap is with the Brownell's facing cutter to be sure that you keep the face of the barrel extension square to the bore. Much safer than trying to stone or file by hand, although a skilled gunsmith can do that. A gap of 0.002 is too snug, 0.003-0.004 is what you want, but up to 0.006 is OK. Over 0.008 you may consider setting the barrel back and refitting. You will lose about 15 f.p.s. per 0.001" above median factory tolerence in this caliber or others operating at similar pressure such as .38 Spl. +P+ and .357.

 

[rcmodel]

I suspect it is/was a cleaning or ammo issue.

As already mentioned, a few specs of unburned powder under the extractor star can bind up the cylinder.

A change in ammo brands may result in cleaner burning.
Ejecting with the gun held muzzle up will help prevent unburned powder getting under the extractor.

Since the gun is probably not going to be used for extended gun fights, I think an .002" gap on a .22 WMR might not be such a bad deal!

It will cut down on the piercing blast noise, and add velocity, which is the only reason for it's being.

rc