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Discussion Starter #1 (Edited)
why do the primers blow out on Fedral gold match 168 SMK in the H&K G3/91 and it's clones ? and yes the head space / bolt gap is in spec .017" and the same rifles have no problem with 7.62x51 nato surp Port,Hirt,Dag,Santa Barbra and Aussy. Is the GM308M brass too soft ? case wall thickness too thin? or do the primers have to be staked? even on my PTR-91 with the match barrel and chamber (early production sn # A0058) it happens . anyone else have this happen ?
 

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Just so I'm clear, is it that the firing pin is piercing the primers, or is it that the primers are popping out of the cases during ejection?

I've shot many different types of primers through my PTR91, and not had an issue with primers coming out of the cases. I've shot the 168 grain Sierra Match kings too. No issues. All of this was loaded in 1960s vintage military brass, however.

If the primers are pierced I'd guess it was the fault of the firing pin being too long. If it were primers popping out of the case my first guess would be that the action is opening too quickly. Second guess is that the case heads on those cartridges were not properly hardened and the primer pockets are expanding excessively, allowing the primers to come out of the cases.

If the action is opening too quickly, and the gap is as you say, then my first guess is the locking lever or locking lever spring that holds the bolt and carrier together when the bolt is in battery.

The FC headstamp 223 cases I've used and examined have issues with proper hardness or perhaps it is alloy, as I can only get maybe 2 reloadings out of them before the primer pockets become too swelled to hold a primer. 308 is not the same as the 223, but perhaps these manufacturing issues have carried over to the commercial Federal cartridge cases as well. If this is in fact the issue, the swelled primer pockets will be evident no matter what rifle they are shot in. The spent primers will pop out very easily, and the pocket will not hold a replacement very well. ... Could be if this is the issue, the "vigorous Vorgrimmler" extraction and ejection simply dislodges the primers in flight?

If you can find the empties it would be interesting to see what sort of tension the primer pockets have when seating a new primer.

Otherwise, your guess is as good as mine.
 

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Discussion Starter #3 (Edited)
what I'm refering to is new factory loaded Fedral gold match 168 grain smk ammo part # GM308M .got it from CDNN 3 years ago or so ,it blows the primer clean out of the case every time . I installed a new locking piece and fireing pin,and spring (real H&K) from RTG just to make sure and it still pop's the primers . I realy think it's the brass fedral use's .
 

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I have not heard of that happening before. I've shot that exact same factory cartridge out of my HK91 and SR9TC and I have yet to see it happen in either gun.
 

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A friend of mine had an SR9T a few years ago that did the same thing. We never did figure out why.
 

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^^^Wow, 2 guys with first hand knowledge of this happening. Really freaky.

At this point I think the best thing you can do is contact Federal and let them know about the problem. I'd send them the batch number and several of the casings for them to look at. Let us know if you find out why this happened.
 

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Discussion Starter #9
After 3 calls to Fedral ,and me leaveing 3 messages that have not been answered I have given up on fedral. all future match ammo will be Black hills .
 

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That's disappointing to hear GONIF, I would have thought Federal would be extremely interested in primers being blown out of the cartridge.
 
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