Any ideas?

[Mattnall]

nny is early Privi brass I think.

Yes, Prvi Partizan. nny is cyrillic for PPU.

[Maggot]

Well I suppose IF a pocket would fail, it would be at the sharpest angle. A bit like the Murom primers burning holes in my ARs bolt face via blowing small holes round the radius.

Its the thinnest part of the case head and is containing, in effect I guess, a small shaped charge. If all the pressure cant get through, the floor is going with it.

IF you dont want that case, I would love it for my occasional re-loading lessons I give friends (just to get them going safely).

[Dahonis]

Well I suppose IF a pocket would fail, it would be at the sharpest angle. A bit like the Murom primers burning holes in my ARs bolt face via blowing small holes round the radius.

Its the thinnest part of the case head and is containing, in effect I guess, a small shaped charge. If all the pressure cant get through, the floor is going with it.

IF you dont want that case, I would love it for my occasional re-loading lessons I give friends (just to get them going safely).

I'm sorry, I chucked the whole batch. Should I get anymore, i will keep them and let you know. I have somewhat of a collection of different headstamps i will go through them shortly aaarggh

[Maggot]

Well I suppose IF a pocket would fail, it would be at the sharpest angle. A bit like the Murom primers burning holes in my ARs bolt face via blowing small holes round the radius.

Its the thinnest part of the case head and is containing, in effect I guess, a small shaped charge. If all the pressure cant get through, the floor is going with it.

IF you dont want that case, I would love it for my occasional re-loading lessons I give friends (just to get them going safely).

I'm sorry, I chucked the whole batch. Should I get anymore, i will keep them and let you know. I have somewhat of a collection of different headstamps i will go through them shortly aaarggh

No worries, I have just never seen it before

[jjvc]

I've never seen that before Chris.
I have a couple of boxes of once fired PPU if you need them. I'll take them to the yarners tomorrow for you just in case.
Gratis BTW.
Joe

Any ideas as to what has happened?

Low velocities cast boolit loads only, reloaded 8 times.

No other damage to the case.

[snayperskaya]

Just a thought but wouldn't the pressure build up from the ignited propellant force the floor of the primer pocket and the primer back against the bolt face rather than them blow through the case and down the barrel?, surely physics would have them moving rearwards rather than forwards?.