Light primer strikes

[chris in va]

I've had my CZ 527 carbine for a few years, 7.62x39. Occasionally it will have a problem with Wolf primers, but today I tried out my new cast boolit reloads and one in three showed very light primer strikes. CZ sent me a new pin spring which helped, but didn't eliminate the problem.

I'm using CCI large rifle primers and trimmed Winchester brass. All rounds 'clink' into the chamber.

One thing I noticed, if I physically turned the lightly struck round by hand about 90 degrees and rechambered, it would get a nice, deep primer strike.

Any ideas?

 

[chris in va]

Here's a little more info, might shed some light.

This is a non-primered dummy round and shows where the round sits in the bolt face when feeding/extracting. As you can see it isn't flush with the face (not sure if that's normal). I did put a thin film of red grease on the case head, and it showed up on the bolt face when I chambered it.




Now here's how far the pin extends.



I took the bolt apart and found the firing pin is threaded, but it's been drilled so the retainer pin won't go in if I unscrew it half a turn. CZ has been less than enthusiastic with past repairs so I'm reluctant to send it in only to have "no issues found" written on the repair order like last time with my 75BD.