trigger lock up on 25-2

[jkmo]

I recently got a 25-2 and replaced the target trigger with a smaller serated trigger. I have dry fired it a 1000 times and it strokes fine. Shooting bowling pins I am getting some trigger lock. Can't move trigger. Open cylinder and it goes away. So ammunition problem? but I don't think so. This gun is an older gun but I have only put about a 100 rounds thru it and it may have been unfired when I got it.

Here's my drill (shooting reloads). Before a match I make sure each round will chamber in the cylinder. I then load a moon clip and put it in the cylinder. I then pull the hammer back and rotate the cylinder making sure there is no binding (high primers).

About 3 or 4 times today while pin shooting I couldn't pull the trigger. Usually happens after 3 or 4 rds are fired. The cylinder / forcing cone gap seems awlfully tight with this gun. I don't have a gauge but it is small.

I wonder if after the 3rd or 4th round the forcing cone is expanding and binding the gun up? I need to get a gauge and see what it is.

I went to the factory armorer school in 87 so I know some but only have done a few action jobs over the years after getting out of shooting for quite a while.

Anyway that's my diagnosis. Any help appreciated. Thanks

 

[scooter123]

Two thoughts come to mind, both learned with actual experience with my 610-3.

First is that the rebound spring you have installed may be a bit too light. I tried a 12 lbs. rebound spring and while it funtioned perfectly in dry fire testing it locked up twice during live fire. The second time it happened it took a bit of wiggling of the hammer to get the rebound slide to return properly. I suspect drive link popped out of it's nest and wiggling the hammer and trigger happened to pop it back in place. Went home and installed a 14 lbs. rebound spring and function has been perfect.

Second thought is dependent on whether your 25-2 has a trigger stop rod inside the rebound spring. As I found out if you install that pin backwards it will lock the trigger up solid, however in my case it was dependent on how the gun was oriented, pointed up it was perfect, pointed down the trigger would lock every time.

Final thought concerns the B/C gap. You can pick up a set of shims for adjusting valve lash at almost any auto parts store for about 6-8 bucks, so next time you are out pick up a set. If you find your B/C gap is less than 0.004 inch it's possible that the barrel is binding on an accumulation of carbon on the face of the cylinder. Personally, I feel that a B/C gap of 0.006 inch is optimum, it's doesn't produce issues with carbon buildup but it's tight enough to produce good accuracy without spitting. If you find the B/C gap is very tight, the solution will be a bit of careful stoning on the rear face of the barrel. As for expansion of the steel being a problem, steel expands in proportion to length and the barrel stub is so short that it's unlikely that it will increase in length by more than few 1/10,000's of an inch. BTW the linear expansion coefficient for steel is 0.00000645in/in/deg F. so in a 100 degree rise in temperature that would relate to 0.000645in/in of length.

 

[Alk8944]

You are shooting double-action, correct? Chances are the trigger is not fully recovering. If this is the case the trigger does not engage the cylinder stop and pull it out of engagement with the cylinder stop notches before the hand is trying to turn the cylinder, that is still locked.

1) Clean and lubricate the lockwork.

2) If the rebound slide spring has been cut or replaced with a lighter one to acheive a lighter double-action trigger pull, replace it with a standard spring.

3) Make sure you are fully releasing the trigger between shots! This may sound silly, but you would be amazed how often this happens, especially if the rebound slide spring has been lightened.

 

[jkmo]

I do have a Wolf mainspring and 12 lb Wolf rebound spring in this gun. I started with an 11 lber and it was borderline so went up to a 12. Maybe it's too light also. I thought about the not releasing the trigger as I was alternating pin shooting with a glock 45.

The stop rod is in the rb slide correctly. I'll step up the rb spring weight and see what happens and also gauge the cyl / fcone gap. The trigger not returning fully is the most probable.

Thanks

 

[jkmo]

I took a couple of coils off a 13 lbr and shot it. Same deal. I put a 14 lb spring in tonite and I think that's gonna do it (good trigger reset). But haven't shot it yet.

I think I was just trying to go too fine with it.

Nice advice. Thanks

 

[jkmo]

A 14 and 15 lb didn't work either. I put the original trigger in with just a slightly shortened original spring and the same thing. The trigger return is real positive. Will only lock up shooting live ammo. You can stroke it as fast as you can (dryfire) and not get it to do it. Seems like it locks up after 4 or 5 shots. Could it be a long ratchet or some type of cylinder stop / trigger relationship problem?

Thanks

 

[scooter123]

Why are you shortening the rebound springs? IMO that's likely a cause or your problem and not "good practice" today with the various weights of rebound springs available. When you reduce the overall lenght of a spring you can greatly reduce the force it can produce near it's full extension. Basically, these springs NEED a certain amount of Pre-Load for the rebound slide to function properly and by cutting them you are reducing that Pre-Load. I would suggest that you try installing a 14 lbs. rebound spring without cutting it's length and see what happens. You also haven't posted what your B/C gap is. With an Autozone or similar on nearly every street corner in America you really can't say you can find valve shim gages, so go out and buy a set, they aren't very expensive.

My brand new 625JM came in with a 0.0025 inch B/C gap on one side of the barrel so the first thing I did before shooting one round was to use a diamond hand lap on the rear of the barrel to produce a B/C gap that was equal on both sides. Now a 0.005 shim slides in freely and a 0.006 shim won't fit, so it's good to go and I've run 300 rounds through it without any cleaning or any issues with the cylinder binding.

Finally, you need to make a bit more effort to diagnose the specifics.

If it's a possible rebound spring issue, try pushing the trigger forward when it locks up. If that frees up the trigger you have a problem with the rebond slide not returning. If so, open up the lockwork and clean the frame recess and sideplate completely. Then look for wear marks from the rebound slide rubbing. If you see signs of a heavy rub, it's an indication you need to stone the rebound slide a bit to reduce that rub.

Second, NEVER assume you have the trigger stop pin installed correctly. The difference between the two ends is so subtle that it's not at all difficult to install them backwards. Personally, I've taken to adding a bit of a chamfer to each end to make them non critical for orientation, however I have no idea if this is factory endorsed so I'll leave it to others to make the call on doing this on their revolvers. One absolutely positive way to confirm if the stop pin is a problem is to just leave it out. It'll lead to a bit more staginess in the trigger stroke but it's not an essential part and not normally used in the K or L frames.

Finally, if you notice the gun starting to bind, unload it and then take a look at the face of the cylinder. If you see drag marks in the carbon fouling, it's dead certain you have a B/C gap that is too tight. I would also suggest you take a good look at the recoil shield. If you are reloading for this gun and resizing primer pockets as part of that reloading process you may have an issue with your re-sizing tool and your primers may be backing out and tying up the gun. I would also suggest you check to make sure the firing pin bushing isn't recessed, if so it can allow primers to back out far enough to cause problems.

 

[jkmo]

The 14 and 15 were uncut Wolfs. The original I just took 2 coils off. When it locks up the trigger is forward and won't go rearward. I don't think it's a b/c gap or trigger return problem. I'm sure the trigger stop pin is in right.

It locked up on the second cylinder the last time I shot it. Gun is clean. No shaving lead or buildup on the forcing cone. Cylinder spins freely with ammo in it at half cock. Haven't resized any primer pockets and it did it last time with factory 230 ball. I'm thinking it a hand / rachet problem but ready to give up and take it to a Smith.

 

[H Richard]

Are your moon clips uniform thickness? Are you using all the same brand brass? Uneven thickness of case heads on brass or overly thick moon clips can cause binding. I wouldn't go below a 14 lb rebound slide spring, and I always keep the factory mainspring. Is the rebound slide nice and smooth where it slides on the frame and the area good and clean and lubed?

 

[jkmo]

The moon clips are new and I have polished the bottom of the rebound slide. Winchester and Remington brass. It doesn't seem to be the cylinder binding and hard to turn, the trigger can't be pulled until I open the cylinder and rotate it.

 

[stang1911]

trigger lock. Can't move trigger. Open cylinder and it goes away. The trigger should not move with the cylinder open! Unless you hold the cyl. release back.

 

[Alk8944]

The moon clips are new and I have polished the bottom of the rebound slide. Winchester and Remington brass. It doesn't seem to be the cylinder binding and hard to turn, the trigger can't be pulled until I open the cylinder and rotate it.

I don't see anywhere where you say you tried pushing the trigger forward when this happens, before opening he cylinder or doing anything else, have you done this? This has all the characteristics of trigger/cylinder stop fitting issues.

When changing a trigger, often the cylinder stop needs to be re-fit to the new trigger. It can be binding on the trigger hook as the trigger goes forward and tries to cam the cylinder stop forward, or possibly the flat over the cylinder stop needs to be cut down very slightly. Try lightly stoning the front and corners of the trigger hook, and the cylinder stop bevel. Use a hard Arkansas stone, the idea is to polish the surfaces, not change their dimensions significantly. DO NOT do too much stoning on the trigger hook, you will go through the case hardening. Any metal removal needs to be done on the cylinder stop which is through hardened, not case hardened.

If this doesn't work send me a PM and we can discuss this further off the board. I will be happy to discuss this with you on the phone.

 

[scooter123]

It sounds a bit baffling. At this point lets just try throwing ideas at the wall and see what sticks.

I really don't think it's possible that it's a hand/ratchet bind because with the trigger forward the hand gets levered back into the frame. Actually, with the mechanical advantage involved due to the placement of the contact points, the trigger has a considerable amount of leverage to pull the hand free.

I would suggest that you conduct an experiment. Try removing the trigger stop pin from the rebound spring. It's quite possible you have one that wasn't machined properly. These are NOT essential and are only commonly featured on the N and possibly X frames so leaving it out won't do any harm. If you find your trigger lock issue has disappeared you'll know the most likely cause. BTW, I'll admit to being a bit hung up over this because I've gotten them in wrong often enough I assume it's the most likely cause for issues like yours.

Another possibility that just occured to me is the you may have a center pin in in the ejector rod that is allowing the bolt to come forward just enough to snag the hammer. It's also possible that there is a tiny bit of a bind in the channel for the bolt leading to the same problem. Next time you have the trigger lock up, try pulling the cylinder release to the rear. If that frees up the trigger you need to have a new center pin fitted to your revolver or remove the bolt and stone down the high spot that's causing it to bind. BTW, the bolt is the sliding part the cylinder release attaches to.

 

[tomcatt51]

Some hands have a lug on them that slides in between the frame and the bolt when the trigger is pulled, to keep the bolt from coming forward under recoil releasing the cylinder. Sometimes these lugs need to be relieved on their back side to not catch on the bolt as the trigger is pulled and the hand (and lug) moves up.

 

[jkmo]

Shot the gun today and it locked up again. Took out the trigger stop. It was in right. When I did a metal fragment came out of the hole in the rebound slide. I have changed springs several times and a fragent like this has never come out. It looked liked shaved steel from the inside of the rebound slide. Maybe thinking there is a flaw in the rebound spring channel and the spring is gouging / hanging up in the slide? I'll fit a new rebound slide and will see what happens. I don't think it's the bolt binding the hammer but forgot to push back on the cylinder release when it jammed to see. I did push the cylinder release forward when it jammed but that did not relaease the trigger.

Any ideas? Thanks for the input.

 

[jkmo]

I tried it with the trigger stop removed and it locked up still.

 

[tomcatt51]

I tried it with the trigger stop removed and it locked up still.

Does the hand have the "extra" lug on it that keeps the bolt from moving under recoil?

 

[jkmo]

The hand has the lug (post) on it. Stone it a bit?

 

[tomcatt51]

The hand has the lug (post) on it. Stone it a bit?

If you run the gun (springs removed) with the sideplate off you should be able to see/feel the lug hit the bolt, if it is. I use a file, the lug's not hard. I put an MIM .400 smooth trigger and a 10-9 (spring loaded firing pin) hammer in my 3" HB 10-8 and the lug, which was fine with the original parts, hit the bolt and had to have ~.030" filed off for clearance. Filing off a little too much for clearance won't hurt a thing.

 

[jkmo]

I'm starting to think the hand is skipping by a rachet under recoil. Anybody heard of this?