cylinder gap

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dashootist

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My "classic" S&W model 14 has too large of a cylinder gap. When I stick feeler gauges into the left side of the cylinder-barrel, I was able to stick a maximum gauge of thickness .010. When I stick it into the right side, I can stick a maximum gauge of .007. Do I take the larger or smaller measurement for the cylinder gap?

I get lead spitting occasionally, less so with nice round nose bullets. I'd like to tighten the gap to, say, .002. How much should a gunsmith charge for this service? I know it's a very difficult job, and that's why I'm asking.
 
The gap isn't excessive for revolvers made to shoot soft lead bullets, and the spitting may be caused by a misaligned chamber and bore rather then the gap. If you want the gap corrected the best bet is to return it to Smith & Wesson who have the special tooling to do the work of removing the barrel, taking a little metal off the shoulder, and setting it back. There is a possibility they might do it as a warrantee repair, although at .010" it is (I beleive) still within their specifications.

Any revolver intended to be used with lead bullets shouldn't have a gap of less then .004 to .006 inches. Too tight is a mistake.
 
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If you do decide to have the gap closed to say, .002" as you've indicated, you might reconsider shooting lead through it. A larger gap will cause you less issues with lead bullets than will something tighter like .002". You'll likely have problems with the cylinder dragging or even locking up. When shooting lead, deposits will quickly start to build up at that cylinder to barrel region. My suggestion would be to have a qualified gun smith take a look at the revolver. You may have a timing issue or other allignment problem causing the lead spitting. Generally speaking, cylinder gap isn't usually the culprit and if fact may just be the reason you've noticed a problem.
 
THe lead spitting happens very rarely. Like once per 100 rounds. Is it possible the stuff hitting my cheek is powder residue or unburn powder, not lead?
 
I have seen plenty of S&Ws that shoot great that have a gap that big. I think that if you are getting lead spitting out, its something else than the gap. It seems odd that you say the gap is smaller on one side than the other, maybe a cylinder misalignment?
 
You go to .002 you may as well toss it in a trash bin. Your gun is in spec. Its a revolver it will toss <deleted> out at times and that is the mater of the beast. 95% of the time the oh its spitting lead issue is people not used to revolvers is all.
 
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dashootist said:
THe lead spitting happens very rarely. Like once per 100 rounds. Is it possible the stuff hitting my cheek is powder residue or unburn powder, not lead?
Click to expand...
I bet you are getting hit by a hot powder. The mouth of the barrel is not cut square, that's why you are .010 on one side and .007 on the other. The barrel would have to be cut square and then set back to the desired gap. I like about .004 minimum.

I have a couple of DW revolvers and have played around with different gaps with their changeable barrels. At .002 you well see dragging after a 100 rounds or so. Gaps larger than .008 well toss a lot of powder out.
 
Years ago I had a beautiful 5" model 27 with the exact same BC gap problem. I sold it and bought a Dan Wesson 15-2 6VH so I could control the gap and have never regretted it. While the DW is far more accurate than the 27, it just doesn't have that beautiful finish and checkering. I keep the gap at about .005".
 
In 3500 rounds, my GP100 has never spit on me once.

I would send your S&W back for spitting. I'm sure S&W would even let you pay the shipping. (They usually pay for shipping, but I'm sure they could abstain if you ask.)
 
Doubt the B/C gap has anything to do with it.

I'd suspect a leaded or improperly cut forcing cone.

First thing to do is carefully inspect the forcing cone for lead build-up, and clean the crap out of it if you find any.

Then inspect it again and see if it is cut centered with the bore and properly angled enough to funnel the bullets into the rifling.

rc
 
#1... it could be lead build up as mentioned, make sure your forcing cone is CLEAN.. the measure it..

If you still have a variant of .03 from one side to the other ... SEND IT BACK TO SMITH !!!

If that cleaned it up, and you are square at .10, your ok.. it is at the top end of the tolerance of .06 to .10... However if that did clean it up, then you have a bad timing issue... lead should not build up on one side more than the other... Send it BACK

The occasional spitting of, or shaving lead.. could be a timing issue, or your cylinder locking lug may occasionally not catch or seat completely... If it is just seating issue for the cylinder locking lug, it is one of two things, a weak return spring on the locking lug. (#1 suspect) or the cylinder locking detents may be a little dirty.. clean them up with a little Hoppies #9 and a soft brass brush,, an old cleaning brush will probably work fine..

If it is the spring, it is not a hard job, and the part is not at all expensive..Brownell's I believe carries them, if not Numeric Arms, however if you have never tech stripped a Smith, I would recommend that you let someone who knows how do it...

If it is a wear or fitting issue with the lug its self, a replacement needs to be fitted by a competent gunsmith.. Someone that KNOWS how to time a Smith revolver and has the tools to do it..
 
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He said he has one of the Model 14 Classic's, which I took to mean one of the new MIM + Hillery Hole ones made in the last few years.

If it's out of time bad enough to spit, S&W should be the only one to touch it.
Afterall, it's a practally brand new gun.

rc
 
Cylinder gap is perplexing to me. Everyone claims that such and such a gap is too big, but my old model 10 also has large and uneven gap. On one side it's .008-ish. On the other side it's .010 to .012-ish. It spits ZERO lead with any of the variety of bullets I've used, lead or jacketed, and is accurate. It's more accurate than my model 64 which has a consistant .006 all that way around.

I guess I'm of the opinion that if it works good, I'm not going to have it torn apart and "fixed."

A model 14 is more of a target revolver than my guns are, so I understand that it may be more of a critical issue with that type of weapon.
 
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Misalignment between a chamber (or more then one) with the bore is much more likely to cause spitting than a high-out of tolerance cylinder/barrel gap. This is especially true if the yoke barrel on which the cylinder revolves, is bent. Occasionally you wii find that the hole in the frame the barrel is threaded into is not straight.

For this and other reasons it is best to send a "spitter" back to the manufacturer, who has the necessary equipment to determine what is causing the problem - and then fix it.
 
I will reiterate what I just said on another thread. You don't want too tight a b-c gap because when a revolver is fired the cylinder heats up and expands lengthwise. If the gap is too tight, the gun will hang up until it cools down. I have seen revolvers with tight gaps bind after firing only two cylinders full.

Jim
 
On two occasions I examined different Taurus, mid-frame .357 Magnum that had tight cylinder/barrel gaps and Titanium cylinders. Both had been fired using high-end loads, and both had the front cylinder face beat up. I determined from the marks that when fired the cylinder stretched enough so that the cylinder actually impacted the end of the barrel hard enough to leave a stamped impression. :eek:
 
1. Also, take 2 large, empty breakfast cereal boxes (or similar), put something in the bottom to give them some weight, and tape a piece of plain paper on the inside/vertical faces. On a shooting bench place a box on each side of the revolver with about 6" of space on each side. Fire the gun, and then inspect the boxes for lead spatter (cuts in the paper) or powder residue (black smears). If necessary, repeat with fresh paper.

2. Try some different ammunition.
 
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