S&W 38 Double Action 3rd Model

[Johnm1]

This was put together with parts but has always had a 'stumble' from time to time since I assembled it a couple of years ago. Every once in a while it will temporarily jam either pulling the trigger double action or pulling the hammer single action. The hammer link pin, the link being the part that the mainspring attaches to, was loose in position and made it a bear to install the hammer. Heavy grease helps. After I assembled it a couple of years ago I knew it was loose but figured the tension of the Mainspring would keep it in place. Once I noticed the stumble I assumed it was that pin that caused it. But being this is such a pain to reassemble I put it off until last night. The below picture show it reassembled and the bright parts show where I shortened the link pin. It is now very secure and much easier to install the hammer.



Here is a close up of the inner action. The lighting made the shiny part disappear. I'm thinking now that the rear sear is the issue. It is somewhat buggered but not on the mating surfaces. Possibly a non mating edge is intermittently catching the frame. Anyone familiar with this model and have any insight?



One last thing, and this may lead to the conclusion that something is assembled incorrectly. I can pull the trigger and reliably set the hammer at the single cock notch. That can't be correct could it?

As much of a pain it is to reassemble this model, I want to have a plan before going back in. I'll see if I can post a video of the action in motion.

 

[Johnm1]

Here is a link to the action in motion. Of course I can't make it malfunction on video. Notice I did show it locking on the single action notch while cycling it in double action. It is a one minute video, so it will take a while to load or download.

https://photos.app.goo.gl/QtVV8JE1LR5WKBSWA

 

[Johnm1]

We can probably rule out the rear sear. I was able to create the lock up and physically moved the rear sear out of contact with the hammer and it didn't relieve the lock up. Only moving the cylinder relieved the problem. I'm now leaning towards this being an issue with the hand.

 

[Johnm1]

This might be the culprit



The cylinder and frame are numbers marched. I can't seem to locate a serial number on the barrel. I can't remember for sure but this started out as a matched barrel, cylinder and frame only. It may have had some other small parts.

If this in fact the problem I'm not sure I want to try to fix it. I have no way to visualize where the actual issue is or how to correct it. It seems more than likely that this is the problem though. I cleaned up the ratchet teeth for the photo and the problem is a little bit worse.

 

[Jackrabbit1957]

I'm not a double action guy so I may be way off base here, thinking the hand may be short, have had single actions lock up due to a short hand. May be worth looking at.

 

[Johnm1]

Yep. My thoughts also. I can disassemble the entire guts, just can't finagle the trigger group out. I'll have to stare at this one for a while. But the symptoms support a worn out hand. Could be the ratchet teeth as well. They are well worn compared to others ive seen.

 

[wiscoaster]

Wow, that's an ugly-looking cylinder. I don't know if there's anything you can do about those ratchet teeth. Try to find another gun that's being sold for parts and hope it's got a better cylinder?