More Yugo SKS problems

[budman93]

After replacing the new valve with a Murray's oversized stainless one as Clandestine suggested it ran great. Then we ran into other problems. Rounds stopped going off and when inspected had not been touched by the firing pin. We took it apart and found that the firing pin had somehow been forced too far out the back of the bolt and although we were able to get it back in I am pretty sure it is now bent. Platekiller will post a pick of it coming out the back of the bolt later.

The second problem is with the trigger group. The hammer is in the cocked position and will not release. I was thinking that maybe when the firing pin got forced back to far it in turn forced the hammer back to far and bent something but I don't know. We pulled the trigger group and I can see nothing visually wrong with it. I 'll have to take a closer look at it and maybe strip it down.

Any ideas on what could have caused the firing pin to do that and what might be wrong with the trigger group?

 

[platekiller]

Photos.





No pics of the fire control group but couldn't figure it out.

 

[budman93]

My photography skills sucked on that second picture. Good thing you got a good one.

 

[Half-cocked]

Looks like it didn't even have a firing pin retaining pin in it.

Show some pics taken from the side of the bolt.

edit: both sides of the bolt.

Your firing pin should NOT protrude that far out of the back of the bolt, if your bolt is put together properly.

 

[LostSoul]

Is the bolt cross-pin present?

 

[budman93]

Side pics of bolt.

 

[Half-cocked]

Your firing pin is installed incorrectly, or you have a faulty/incorrect firing pin. The flat on the side of the firing pin has a ridge in the middle that should prevent it from ever extending that far out the back of the bolt.


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[platekiller]

The pin is in place. That's why we were confused it looked fine but the firing pin was too far back.

 

[Half-cocked]

This is the farthest that the FP should extend from the rear of the bolt:



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[Half-cocked]

The FP has flats on three sides.

Only ONE of those sides has a ridge, which is blocked by the FP retaining pin, and prevents it from sliding too far out the back.

Yours is in wrong.

edit:

Also, the hammer might be jamming up underneath the rear of the FP, since it's sticking out so far - causing your suspected trigger group problems.

 

[bkraft]

Maybe the pin wasn't put in correctly when you replaced the retainer? There's a bump on the pin that the retainer actually catches and it's possible to put the bolt together with the firing pin rotated wrong. That will cause more movement in the pin then normal.

That would be my first thought.

Just my $.02, did you soak the trigger group in mineral spirits or something and make sure you had all the Cosmo out? I've had that cause strange firing conditions on me before.

If it was me and I had ordered that piston from Murray's, I would have also ordered a trigger, hammer, and sear as well as a spring kit and sprung firing pin as well. I've dropped Murray's stuff into many of my SKSs and absolutely love it. Trigger feel greatly improved, clean breaks... I don't think the sprung firing pin is a necessity, but I've got guns with and without it and I do really like it.

 

[clandestine]

Is there a buffer in the gun? If so remove it.

Remove the firing pin and retainer pin and post pics, the retainer pin may have just failed.

The hammer wont drop till the disconnect lever in front trips first. If that got bent it won't release.

 

[wilcam47]

The FP has flats on three sides.

Only ONE of those sides has a ridge, which is blocked by the FP retaining pin, and prevents it from sliding too far out the back.

Yours is in wrong.

edit:

Also, the hammer might be jamming up underneath the rear of the FP, since it's sticking out so far - causing your suspected trigger group problems.

check the sear to trigger bar. see if its hitting the sear..You can drop the hammer with the FCG out just watch your fingers as it does hit hard. Just make sure your hammer is locked back when you go to install it back in the gun.

 

[platekiller]

Is there a buffer in the gun? If so remove it. Remove the firing pin and retainer pin and post pics, the retainer pin may have just failed. The hammer wont drop till the disconnect lever in front trips first. If that got bent it won't release.

No buffer. He will have to post pics as we didn't have the tools to disassemble the bolt when we were shooting

 

[budman93]

The FP has flats on three sides.

Only ONE of those sides has a ridge, which is blocked by the FP retaining pin, and prevents it from sliding too far out the back.

Yours is in wrong.

edit:

Also, the hammer might be jamming up underneath the rear of the FP, since it's sticking out so far - causing your suspected trigger group problems.

Just stripped it. The pin was in correctly. The pin is slightly bent near the ridge and the ridge was force past the pin, scraping off a small sliver of metal.

 

[platekiller]

check the sear to trigger bar. see if its hitting the sear..You can drop the hammer with the FCG out just watch your fingers as it does hit hard. Just make sure your hammer is locked back when you go to install it back in the gun.

I couldn't get it to drop when we took it out

 

[Dave91]

Sounds like you got a lemon.

 

[Half-cocked]

Just stripped it. The pin was in correctly. The pin is slightly bent near the ridge and the ridge was force past the pin, scraping off a small sliver of metal.

This would have happened if the FP was installed incorrectly, with the ridge behind of instead of in front of the retaining pin, and repeated hits from the hammer drove it in.

All you need is a new FP, provided the retaining pin hasn't lost any metal too. Then it should be good as new.


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[budman93]

here you can see that the firing pin is slightly bent. The retaining pin seems fine but in person you can see where the ridge on the firing pin scraped past it. there was also a small sliver of metal that looks like it came off the ridge on the firing pin.

 

[clandestine]

Just stripped it. The pin was in correctly. The pin is slightly bent near the ridge and the ridge was force past the pin, scraping off a small sliver of metal.

Time to get a new firing pin and retainer