Cylinder Gap Too Tight?

[Caboclo]

I have a Taurus 608. Bought it used, don't know it's history. Every dozen rounds or so, I have to wipe off the carbon from the front of the cylinder, or else it binds up against the barrel and won't turn. Same results with various different factory ammos. Is the gap actually too tight? Should I get a smith to back it off just a bit?

[Radny97]

Following.
(I have a similar question with one of my revolvers.)

[wpsdlrg]

That (that the forcing cone/ cyl. gap is too tight) is a likely cause. However, it is NOT the only possibility. When you say that the cyl. won't turn, do you mean that it is bound up ? Or, can it be turned by hand with little resistance ? If the cyl. is bound up, the the problem is probably tight clearance. You can check this visually, as well as with feeler gauges. If the gap looks really tight, as in thin as a sheet of paper tight, then the gap is probably too small.

What you said about wiping off the front of the cylinder temporarily freeing up the cylinder is significant - and MIGHT be clear evidence of the gap being too small.

However, another possibility is that the cylinder is binding internally. Tauruses are funny, different from Smith & Wessons for example, in that the cylinder does not free wheel - and thus is more resistant to being turned, even when nothing is wrong. Does the cylinder turn freely when open ? Try turning it also, when open, while pulling toward the rear....then again while pushing forward while turning it (while open). If no binding is detected, then this possibility can be eliminated.

Finally, if the cylinder can be pushed forward and rearward (when closed) a significant amount.....more than a few thousands of an inch....then this could potentially be the problem. This "slop" is referred to as end shake - and it can cause a revolver cylinder to skip timing and not index to the next chamber every time it should. It can also cause a cylinder to turn only part way to the next chamber. Do check for excess cylinder movement. This is the least likely of the possible causes of your problem - but it is possible.

Based on the results of these tests, you should be able to diagnose the problem yourself. Being that the gun is a Taurus, some gunsmiths won't touch them. So, you might end up having to send the gun back to Taurus for repair. If the forcing cone simply needs to be cut back (to enlarge the gap), this can be done by you, with the right tools. But, don't attempt it yourself without knowing how it should be done properly.

Hope this helps.

By the way, the function tests described above are the same for every brand (and model) of revolver.

[Will-j]

Cab: Look on the positive side....A tighter gap will give you a little higher velocity, due to less pressure loss as opposed to more pressure loss from a wider gap.
Carry some steel wool or 220 grit emery/wet-or-dry paper with you and keep the cylinder face cleaned often. The gap will widen on its own over time...from normal use/wear-and-tear.

WILL.

[g.willikers]

The cylinder can probably be shimmed slightly rearward for additional clearance.

[F. Guffey]

Is the gap actually too tight? Should I get a smith to back it off just a bit?

purchase a feeler gage, measure the gap between the cylinder and barrel for the chambers.

F. Guffey

[James K]

The optimum barrel-cylinder gap is about .006"-007". Some folks say less, because they are thinking only of velocity loss, but much less and when the cylinder heats up it can expand and bind. I suspect that is what is happening rather than the carbon on the cylinder. When you stop to wipe off the carbon, the cylinder cools down and the gun is back to working again.

Jim

[reddog81]

You mention that cleaning the cylinder doesn't help. What about the barrel/forcing cone face? Could that be dirty and have buildup. I would try scrubbing that area with a bronze brush.

[Caboclo]

Thanks for the knowledgeable replies. The cylinder turns freely while open, even while pushing/pulling. Just enough end play to feel. The gap does look very thin, thinner than paper, but I don't have any feeler gages at hand right now. Over-all the gun looks nearly new; maybe I'll just shoot it a bunch more and see if it breaks in.

[AK103K]

I had a couple of Ruger Blackhawks that had the issue, and it was fouling on the face of the cylinder. All it usually took, was a couple of cylinders full, and especially with lead rounds, and many times you could not thumb cock the gun. They went back to Ruger, and they corrected it.

Another possibility, and especially if you dump your empties "muzzle down" (not proper form, by the way ), is you have crap under the extractor star, and it causes the star not to seat properly, and the case rims, to drag on the shield. You'd be amazed at how little the amount of fouling under the star, can cause this to happen too.

[Aguila Blanca]

Originally Posted by Caboclo

Thanks for the knowledgeable replies. The cylinder turns freely while open, even while pushing/pulling. Just enough end play to feel. The gap does look very thin, thinner than paper, but I don't have any feeler gages at hand right now.

You cannot diagnose this issue without feeler gauges. Period.

You can get an inexpensive set at any auto parts store.

[lunger]

Quote "Another possibility, and especially if you dump your empties "muzzle down" (not proper form, by the way ), is you have crap under the extractor star, and it causes the star not to seat properly, and the case rims, to drag on the shield. You'd be amazed at how little the amount of fouling under the star, can cause this to happen too"

Does this happen on an empty cylinder also?

I have a Taurus RB 44 that when new had tight rotation when loaded . A trip back to Taurus did not solve the problem. It ended up being the extractor star protruding too far from the rear of the cylinder. A little hand fitting an it was good to go.
Just something else to check.

[James K]

"You cannot diagnose this issue without feeler gauges. Period."

Maybe not period. Ordinary printer paper is .003"; if a piece of paper won't fit between the barrel and cylinder, the gap is too small. Two pieces will give .006", about optimum.

Jim

[Ozzieman]

Had the same exact issue with a Taurus 445 stainless in 44 special.
Two cylinders and it was hard to cock the gun in single action but less than double.
I bought the gun with that issue from a friend that gave up on it. Good gun smith looked at it and found that the clearance was not only too tight but was not straight to the cylinder.
He flattened the forcing cone to the cylinder and opened it to .008. He didn’t want to open it up that much but had to to get it straight. Turned out to be good little gun. Still have it.

[wpsdlrg]

" The cylinder can probably be shimmed slightly rearward for additional clearance."


Unfortunately, not Tauruses. The cylinder assembly is put together in such a way that it is very difficult to take apart without damaging the internal spring. The design is not really intended to be user serviceable. It would be nice if Taurus cylinder assemblies were like Smith & Wessons.....but regretably, they aren't.

[Hal]

I used to screw around w/my Dan Wesson .22's cylinder gap & sometimes it would bind up like you describe.
I'd get it to a gun smith or back to Taurus to have the try to open the gap.
It's not good for much except a range toy as it is.

[ScaryWoody]

If I shoot several reloads quickly out of my SP101 it would bind. There will be a build up of powder residue on the forcing cone and the heat will cause the gap to narrow. Make sure you really clean the chambers and the forcing cone. I gently use my wife's old multiple sided nail file/polisher.

[TomADC]

Had the same problem with a Liberty SAA made by Pietta in 45 colt, brand new gun that sat in my safe 5-6 years before going to the range. locked up after maybe 6 rounds, turned out cylinder gap was .002 had the cylinder faced to open gap to .008 was great after that.