Is Prvi brass thicker than some others?

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I have read a number of times on various forums that Prvi Partizan (PPU/NNY or Grafs/Highland) brass is thicker than most American brands and as a result has less capacity (this comment seem especially common for .308 Win and that may well be true for that cartridge).
I did a quick, anecdotal and non-scientific comparison for 6.5x55 brass. I compared a few cases each of Winchester and Prvi (NNY stamped). Both were trimmed then fired in my Tikka so case expansion should be the same insofar it may affect capacity.

On average the NNY cases were lighter than Winchester. Winchester average about 189-193gr per case, NNY were 182-186gr for the few that I weighed. Could be different alloy densities?

Next I filled a NNY case to the mouth with H110 because it is fine grained and tapping the case should make a nice dense load. I tapped it until it would not settle any more, filled flush with the case mouth. The same loads would not fit into the Winchester cases, despite tapping/vibrating etc. On average the NNY brass held about 1.5gr of H110 more than the Winchester brass.

In 6.5x55 it would appear that Prvi brass is not necessarily thicker, heavier or with less capacity than Winchester, at least for the few I tested. I don’t have any Prvi .308 to compare to Winchester.
 
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Measuring brass weight after firing in the same rifle and being the same length WILL tell you case capacity. The tiny differences in alloy won't make enough difference to the weight for it to matter. If X brass weighs heavier than Y brass, X brass has less capacity.

Now all the people that swear you have to measure with water and fight bubbles and the miniscus are going to chime in and say I am wrong.


I have tested this and it works, plain and simple. And, so have you.
 
I've read that it is thicker than most US brands not not all. Lot-to-lot inconsistencies with any manufacturer will change things. The more important thing I've read is that they have consistently harder case heads so resist primer pocket loosening with upper-end loads more than most US brands of brass. Lapua and NATO brass is similar in this regard.
 
I have 100 PRVI cases in 7x57. They are practically identical in weight and volume as the Winchester cases I have.

On the other hand, the Remington cases in 7x57 weigh, on average, 30 grains more, and have substantially less capacity.

I also have 100 RWS cases, which weigh just 5 grains more than the PRVI and Winchester cases.

Regards, Dave.
 
I have some in .223,7.62x39, 7mm-08, 6.5x55, and 8x57. It is definitely thinner brass then most, Winchester is the closest N/A brass to it and it is just slightly heavier on average (few grains) in my applications anyway.
 
PPU 7.62x51 head stamped brass definitely has a thicker rim than win, rem, fed 308. I haven't measured ppu brass at the web or neck or for case capacity. It is good brass, primer pockets and flash holes need no uniforming and I het 10-20 loads out of them provided I aneal every 4 rnds.
 
I found PPU brass thinner in general but much harder than Win,Rem or FC brass.I use hand press and difference is very noticeable.
Exception was one lot of 8x57 where brass was both thicker and harder.I adjusted load but that lot is still not as good as other one I had before.
I'm shooting it for last 4 years and anneal once a year.Out of 50 cases only 3 necks cracked so far.Very long lasting brass even if not match quality.
 
Cleftwynd said:
Measuring brass weight after firing in the same rifle and being the same length WILL tell you case capacity. The tiny differences in alloy won't make enough difference to the weight for it to matter. If X brass weighs heavier than Y brass, X brass has less capacity.

Now all the people that swear you have to measure with water and fight bubbles and the miniscus are going to chime in and say I am wrong.


I have tested this and it works, plain and simple. And, so have you.
Click to expand...

I agree that just weighing the cases will give you an accurate indication of the case volume. I have several loading manuals that indicate military cases are heavier and have less capacity. In the 308 cases I have found that for every 10 grs heavier a case is the capacity is reduced approx. 1 gr of powder. I have found that MOST military cases are approx. 20 gr heavier than commercial cases and that max loads in military cases are approx. 2 grs less than commercial cases.
 
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