Cylinder latch sticking 1917

[ydennekb]

I picked up a pretty good shape 1917 a week ago and it's having an issue with the cylinder latch. With the cylinder open or closed, when I push the latch it sort of snaps into place. It opens the cylinder fine, and locks the cylinder closed fine as well. I took it out and cleaned a bunch of old grease off of it and ran some 800 grit sandpaper over it to knock any burrs off. So I took it out shooting today, and when firing double action, the latch would move forward and block the hammer so that I can't fire the next round. I would move it back into place and fire again, same result. The ejector rod is tight and straight as best I can tell. Weird thing is it wouldn't happen when I'm shooting single action, I'm assuming that's because my grip may be slightly different.

Anybody heard something like this before?

 

[OldChief]

Assuming your revolver is a Smith and Wesson and not a Colt. The bar inside the lock works that the thumb piece moves (the bolt) has a very small spring in the rear end. That spring may be broken or missing.

 

[ydennekb]

It is a S&W, the spring is present and functional. When moving the release fore and aft, it doesn't slide like every other Smith I've owned, it snaps into position and stays there unless I'm shooting, at which point it moves forward. Not enough to release the cylinder but enough to block the hammer's rearward movement.

 

[walter o]

I have seen the hammer becoming stuck on the cylinder lock because the hammer was hanging up on the side of the lock assembly . pull outward on the thumb latch piece ,see how much play .Push IN on the thumb piece and see if the hammer hangs up.

 

[ydennekb]

Tried that, there is zero in and out movement. I made a short video of what's happening, see if this works. You can see that it essentially has three positions. I push it to the back and after it snaps the latch moves forward. When live firing the latch goes forward enough to block the hammer but not release the cylinder. In the video after the latch moves forward I actually pushed on the other side with my trigger finger to make sure the cylinder was not released.

Guess that didn't work, try this link
imgur: the simple 404 page

 

[walter o]

How long have you had the gun? i might be suspicious of the previous owner Changing or tampering with the ejector rod or the cylinder bolt .if you recently purchased it. As far as i know the ejector rod should rest on and put tension on the cylinder bolt.

 

[steelslaver]

I would check the ejector rod springs and the barrel lug and its spring. Make sure the latch and its bolt spring are 100%, hole clean and slides smoothly without the cylinder closed. Does the latch stay straight in its slot.

In other words I would go over everything that moves witth or from the latch movement.

 

[ydennekb]

Well I took it all apart and tried each piece separately for function and everything was fine until I started screwing down the side plate and I've narrowed it down to this screw closest to the rear of the trigger guard. I can tighten it to a point and the cylinder latch starts sticking, back off and it goes away. I couldn't see any unevenness in the sideplate using my uncalibrated eyeball. Does this change any diagnosis?

 

[Protocall_Design]

It sounds like the tail of the bolt is getting pinched between the sideplate and frame, a minor fitting job. See if the bolt is making marks on the inside of the sideplate. If so, you can remove a few thousandths with a file to free it up.

 

[ydennekb]

It is leaving light rub marks on the sideplate, but the bolt and the marks are opposite the screw (across a horizontal axis). I will give that a try.

 

[armorer951]

If the bolt is binding on the sideplate, you should be able to see a contact point, or rub mark on the plate caused by the top of the rear leg of the bolt.

If you have already removed and cleaned the bolt and the bolt channel, and there is evidence that the bolt is binding/rubbing on the sideplate, you may be able to restore function by removing a small amount of material from the top of the rear leg of the bolt. This should allow you to tighten the sideplate screws without causing interference from contact between the bolt and sideplate. (686 no dash sideplate shown)

 

[Hondo44]

Did you remove the tiny screw that holds the tiny spring and plunger in place in the back end of the bolt?

Is it screwed all the way in and does that screw head line up with the rub marks on the side plate?

With the cyl open check the spring tension of the ctr pin by pushing in on it at the ctr of the ejector star. The little spring in the front locking lug does not provide enough tension if the ctr pin spring is missing or installed backwards on the pin.

 

[steelslaver]

Now there is a handy dandy illustration.

That and a couple marks to look for small rough wear spots on bosses around stud holes and you have a what to look look for to smooth up triggerr to. Excellent

 

[RVRSMITH]

Sounds like a center pin spring. Either extreamly weak or missing!

 

[ydennekb]

I ended up stoning down the rear of the bolt that was rubbing on the side plate and lightly sanded the corresponding spot on the side plate, worked like a champ.