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Anyone use Privi brass, 7.62x54r with it’s oversized ignition hole? I come into a box of Hansen brand brass which I believe is Privi it has two inverted “u”s and a “y”. The ignition hole is .094 thou and the Win brass I have is .082. When I fired this ammo which was very accurate I noticed that a few of the primers were slightly ruptured in that the primer indent was cut free of the primer and I could pull out the entire dimple as if it were a cork from a bottle. This was only on two out of 20. I chalked it up to a hot load although it felt fine and the bolt opened easily. Perhaps this huge ignition hole was the culprit. I am not sure how to proceed with this brass. I can always use it with 2400 and cast loads but I am sure I must batch this brass from my regular supply. Any of you run into this? Anyone use the Priv brass that Graffs is offering? Thanks, JB
 

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Prvi Partizan brass(nny) is all I use in many of my milsurp calibers,never had a primer failure like that.
I did have primer craters from the 7.62x54R 180 soft point Prvi factory load being a hot load but that's about it.
 

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Correction: GREAT brass, in x54r and 7.5Swiss both. The only "issues" I've had with the primers on Privi brass is re-priming after the first firing: VERY tight. Once I removed a very small amount of metal (apparently a military style crimp) they primed easy as pie.
 

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Discussion Starter #6
So none of you have any concern or variance in your loads with respect to the huge ignition hole? I wish I could remember the relationship to increase in dia. = twice the flow. I seem to recall that a small increase in pipe dia. would double the through-put. This hole is as large as the holes I drilled out in 45/70 brass for loads with black powder! When I followed that advice I was cautioned never to use that brass for smokeless after making the adjustment. JB
 

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Sounds like a primer problem to me(two out of 20),did you try different primers?
I use Winchester primers without any primeing problems or failures.
My flash holes measure .084" if yours are .094" that's a bit larger.
Yes,it's true if hole is enlarged you get higher pressure as in your .45-70's,hotter ignition more powder burned=higher pressure.
If you don't feel comfortable with them download them by 10% or recycle them,money towards Lapua $72 or Norma $102 per 100 cases.
 

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I have used Prv Part brass for 7.62x54R with no issues associated with the flash hole diameter. The only issue I had was already mentioned, tight primer pockets, which were also a bit deep for my tastes.

I am still considering the concern over the diameter of the flash hole and pressure, or more correctly force. (Pressure is evenly distributed in a pressure vessel per Newton) P=F/A, therefore F=P*A. A=Pi*r*r. r=.094/2, or .047", so A=3.14*.047*.047=.00694 F=50000*.00694=347# versus 277# for a .084 dia. I could be wrong, as it is late, and my math skills leave me after a while.:rolleyes:
 
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