Factory Ammo Pierced Primer

Brown Dog · #1 08-06-2007, 12:09 PM

Took part in sporting rifle competition on Sunday, 100 and 200m, 40 shots at a variety of animal targets, all shots sitting with sticks.

I was unable to shoot at 3 target exposures due to sorting out a failure to fire.

The failure to fire followed a pierced primer (see pic).

Testament to the AW that, after a bit of bolt jiggling (but not stripping) it continued to fire....despite having a piece of brass inside the bolt assembly (see pic of what came out when I stripped the bolt yesterday evening).

Not sure what to put this one down to.....a brittle primer?

BountyHunter · #2 08-06-2007, 12:47 PM

What action?

What caliber?

What Primer?

Factory or reloads?

BH

Brown Dog · #3 08-06-2007, 01:05 PM

Quote:

Originally Posted by BountyHunter

What action?

What caliber?

What Primer?

Factory or reloads?

BH

AW ( = Accuracy International, Arctic Warfare)

308 (there's a bit of a clue on the case heads in the pic

)

Post titled ' Factory Ammo Pierced Primer'

(but to answer your question more fully: Sellier and Bellot Factory Match (launching 168 SMK) )

....doesn't look like a high pressure issue to me...no gas fouling of the bolt...not seen anything like this before. As I said earlier, not sure what to put this one down to.....a brittle primer?

BountyHunter · #4 08-06-2007, 03:07 PM

PICs will not open for me.

sounds like either the ammo was loaded hot and might have soft cup primer and/or you have an issue with the firing pin length and or firing pin hole diameter.

If it does it with other ammo, then you more than likely will have to have the firing pin protusion measured and maybe the firing pin hole bushed.

Get a smith to check the firing pin.

BH

davewilson · #5 08-07-2007, 04:46 PM

i agree with too much clearance on the firing pin and bolt hole.

HeskethPritchard · #6 08-20-2007, 07:46 AM

Me being a mere mortal with very little "gunsmithing" experience would someone please explain to me why the firing pin hole diameter could cause such a failure? I am not trying to be arguementative, far from it, I just don't understand the physics of it and why it would cause a hole in the primer cup. I understand the issue about the firing pin length just not why the FP hole diameter is important.

HeskethPritchard · #7 08-22-2007, 07:01 AM

DaveWilson

Can you help me in my quest for knowledge on this one????