"Recessed" primers and Mauser firing pins

[Col. Plink]

I have a Romanian contract Czech VZ-24 Mauser, and have been having trouble with ammo with recessed primers. By recessed I mean they are not flush with the face of the head. It does fine with everything else, but I'm wondering if an adjustment is warranted, or not advisable, or this problem with ammo is rare. It seems to be true of most of the Yugo surplus I'd like to make use of in the rifle.

Any advice is appreciated!

 

[morcey2]

Get a stronger firing pin spring. It's not just that the primers are recessed somewhat more than necessary, but they're also very hard primers. I picked up the Wolff 24 lb spring (I think; I'll check my notes when I get home) in my first VZ-24 and the misfire problem went away. Before you do that, make sure that the workings inside the bolt are clean.

Primers are supposed to be a couple-thousandths below flush with the case head, but Yugo surplus (1950's through 1970's) have it seated very deep. You don't want primers flush with the case head and someone at the PPU factory decided to overcompensate.

As a side note, I had a 10-second hangfire with one round before I got the new spring installed. That'll wake you right up!

Matt

 

[carbine85]

Have you disassembled the bolt? They can have harden cosmoline inside and that will cause light strikes. Also check the firing pin protrusion.

 

[gpb]

Do as suggested by carbine85 in post #3. Make sure that the internals of the bolt are clean. If that fails have a gunsmith check firing pin protrusion and headspace.

 

[NCsmitty]

As mentioned, old cosmoline in the bolt body can slow down the FP and even impede the full stroke of it. Normal FP protrusion should be .055-.065".


NCsmitty

 

[200Apples]

.
Anyone know what the firing pin protrusion should be from the CZ 527 "mini-mauser" bolt?
I too have had some light-strike issues w/ certain rounds of 7.62 X 39...

Thanks, in advance.

 

[Col. Plink]

Apples - that's good info for me too. Like the sig; Korematsu v US?

Never had the problem before with same ammo, so it'll get a new spring and a cleaning.

 

[200Apples]

.
Thank you, however I only borrowed the quote from another Californian. While we're at it, I think your username to be one of funniest I've ever seen. Bravo! I've been plinking most of my life, and I too enjoyed Hogan's Heroes on television back in the day. Hee!


The quote is from opinions in the case of the West Virginia State Board of Education v. Barnette 319 U.S. 624 (1943) and "...was a case in which the United States Supreme Court held that members of the Jehovah's Witnesses could not be compelled to salute the flag of the United States."

http://en.wikipedia.org/wiki/West_Virginia_State_Board_of_Education_v._Barnette


Now then: there are other contributors to any 527 light-strike issue, such as debris (even a stray piece of pine needle...) in the bolt-stop of the receiver or a weak firing pin spring... both have been looked at and while a spring replacement may become necessary for my carbine, the firing pin protusion measurement would be good to know. I have access to the appropriate measuring equipment (but not to any headspace measuring paraphernalia...).

Please pardon the topic swerve!