Cylinder binding on a 19-4


PDA






LawofThirds
March 5, 2010, 01:33 AM
I recently picked up a very nice 2 1/2" P&R 19-4 in nickel. Cosmetically it had a few issues but it locks up nice and tight and has a super slick trigger.

Today I took it to the range and after ~30 shots I ran a few Hornady 158 grain XTP .357's through it. On the third one it bound up tight. I expected a loosened ejector rod but it wasn't. The cylinder would not rotate and the action was locked up with only 1/8" movement available on the trigger. After carefully wiggling the cylinder back and forth the gun freed up. On the head of the fired case was a bright mark where it had rubbed hard against the firing pin shield.

It has shown a few rub marks on some 125 grain .38's loaded to just below +p as well, but none of them bound.

Is this a case of too tight tolerances? This gun is very tight, the cylinder has no forward/back play AT all (my other smiths and taurus have a very, very tiny amount of play forward and back when uncocked) and I was wondering if that, coupled with the recessed head of the cylinder bound it up.

If you enjoyed reading about "Cylinder binding on a 19-4" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
aHFo3
March 5, 2010, 02:51 AM
I just recently had the same issue with my 19-3. Mine didn't bind completely, but there was some extra friction going on somewhere. The somewhere turned out to be a small burr on the edge of the firing pin hole. I'm not sure how that burr got there, but it was enough to bind up the works.

LawofThirds
March 5, 2010, 03:33 AM
That's certainly something that I hadn't thought about. Was your burr visible to the naked eye or able to be felt?

- Just checked mine and there's no visible/touchable burr, the scrape marks on the head of the bound round were primarily in the primer though. Is there a chance that blast shield is too far forward? if so, is there an easy fix?

The Bushmaster
March 5, 2010, 10:19 AM
You might have a look at the cylinder to barrel fit too. After 30 rounds (?) you may have accessive carbon build up due to dirty powder residue and a close fitting cylinder to barrel gap...

stork
March 5, 2010, 04:15 PM
Lift your extractor star up fully and clean underneath. From the sounds of it you might have a granule or two between the cylinder and extractor star. Sounds weird I know but I've seen only one flake of powder bind up a cylinder.

Vonderek
March 5, 2010, 05:47 PM
Had the same issue with a Mod. 13. Clean gun with not a speck of dirt under the extractor and locked up tight. I removed the crane and cylinder and reassembled and it works fine so I don't know what the problem was. So much for the revolver's legendary reliability!!

LawofThirds
March 5, 2010, 06:42 PM
Extractor star was squeaky clean underneath, I had detail stripped the gun, cleaned and relubed before ever firing it.

Looks like I need to pick up some feeler gauges and find out what my cylinder gap is, it will not fit an unfolded dollar. If it's excessively tight, can it be fixed easily?

Oro
March 5, 2010, 07:00 PM
The next step I think is determining if the yoke is bent. Spin the cylinders one by one, observing the b/c gap on each one. If one or two are excessively tight compared to the others, you may have a bent yoke. Opening the cylinder and spinning it while observing the ejector rod can usually reveal any bends in the ejector rod.

Since you already checked the extractor, here are other things to check:

1) Free operation of the locking bolt - this is the small spring-loaded stud near the muzzle in the end of the ejector shroud. If stiff, soak with penetrating oil then lubricate; repeat until it move freely with light pressure.

2) Ejector rod loose. Check it for tightness. If loose, degrease both threaded ends and finger-tighten with blue loc-tite.

3) Cylinder yoke barrel is secure. Check tightness of frame screw on right side below forward edge of the cylinder.

4) This should be obvious but let's check it - the firing pin bushing should not protrude past the recoil shield. Make sure it's not damaged.

If it's excessively tight, can it be fixed easily?

By a knowledgeable revolver 'smith with the proper tools, - yes. A 15 minute job. Too-tight b/c gaps did leave the factory, especially in the '70s. You also want to gauge the gap right vs. left, and top vs. bottom to see how square it is relative to the cylinder face. If the gun was ever shot very much, this problem should have been apparent long ago.

If you enjoyed reading about "Cylinder binding on a 19-4" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!