WH 1927A1 stuck firing pin

[TennesseeTaylor95]

Good morning everyone. I have stumbled across a new phenomenon with my West Hurley made 1927A1 when I was trying to disassemble it. I pulled the bolt back to check that the chamber is clear and pulled it far enough back to fully cock the gun, so I figured that I would dry fire the gun to be able to disassemble it. However, the Thompson gods mush be against that idea and now no matter how much I pull the trigger, the firing pin won't release. Do you guys have any ideas on how to resolve this? This is the first time I have had this happen so I am all ears on what is causing this/ how to fix it. Thanks!

[DARIVS]

It's not possible to determine what's wrong without more details, and photos. Could you post a picture of the sear surface of the firing pin and the sear located in the lower grip assembly? Are you saying that the firing pin is stuck at the rear, and the spring won't push it forward when the trigger is pulled?

Edited December 29, 2021 by DARIVS

[TennesseeTaylor95]

I would be happy to take pictures of the internals of the gun, but I cannot get the gun field stripped due to the gun being in the cocked position (bolt, trigger, and trip all move freely) with no way of releasing the firing pin no matter how many times I pull the trigger while the gun is on fire. I can lock the bolt back just fine with the trip and release it. The firing pin is fully intact and moves with the bolt from the cocked position, backwards to the position where the bolt is held open. The situation seems as if the sear isn't dropping far enough down to release the firing pin. I am not an expert on this, but I assume that this could be an issue with the lifter if it is jammed or broken, or if the lifter spring is jammed or broken.

[68coupe]

I had this issue with my Kahr, after installing a new firing pin. Remove the safety lever, and depress the sear through the hole with a small screwdriver. If this doesn't work, you may have bigger issues.

 

Hope this helps/works,

Karl

[TennesseeTaylor95]

Thanks 68coupe, I will give that a go.

[DARIVS]

I have replaced the firing pin before, and Kahr does not have good quality control with regard to tolerances with regard to that part specifically. In my case, the firing pin was too thick to fit easily in the slot of the bolt. The sides were sanded and polished until it moved easily in that slot. Kahr makes the firing pins out of high carbon steel plate and they don't watch how think they make them, and they don't make the upset edges of the stamping flush with the surface of the piece, which causes binding. It's a crude, low quality part. You are correct in thinking that the sear surface of the firing pin may be too low such that it cannot disengage from the trigger sear. That's how bad the tolerances from Kahr are for this part. You may have to take a light cut off the firing pin sear to re-establish its ability to disengage and allow it to move forward when the trigger is pulled. I can't remember if I had to do that on mine, but it's definitely a possibility.

 

I took pictures of my assembly below. Check to make sure your sear surfaces on the sear in the grip assembly and the firing pin are not damaged while you have it all apart. Perhaps you may see a difference between the sear on my firing pin and yours.

 

 

 

Edited December 29, 2021 by DARIVS

[TennesseeTaylor95]

Success! Thanks 68coupe and DARIVS for the suggestions and help here. I am now looking at the parts and you can see the firing pin sear engagement surface is not square and has pushed material on the sides of the firing pin where the sear engages it. The little burrs were not there before and I assume that the firing pin is the main culprit here as I don't see any new issues with the rest of the gun. However, is the lifter also the weak link since it is not lifting the sear up enough to release the firing pin? What do you guys think?

[deerslayer]

If your fining pin is stuck back take the safety out and use a small screwdriver to push the sear down further than the trigger pull will allow. That will usually allow you to release the firing pin to do the disassembly. if that's how your gun is currently functioning you will need to remove a little material from the firing pin so that the trigger pull will do its job. Don't go too far on removing material. You want it to release at the very end of the trigger pull. if it releases too easy or too early you will get jams or run on fire. Edited December 29, 2021 by deerslayer

[TennesseeTaylor95]

Thanks for the response deerslayer, that did the trick. I did take a stone to the small burs that I could feel on the firing pin's sear engagement surface and I put my frame parts in the converted 1928A1 frame, and now I have am able to release the firing pin by pulling the trigger about 90%-95% of the time. It is weird, if I leave the gun cocked for a few minutes, I will pull the trigger and only get a click without the firing pin going forward but it will release the firing pin on the second pull of the trigger. Then, if I just continously cycle the bolt as if I were shooting it, the firing pin is released every single time. Overall, it is intermittent and the more I cycle the gun and dry fire it, the more reliable it becomes. Very weird.