7.62 x 54mm question


#1

The 7.62mm type L cartridge pictured in the centre is 2.5mm shorter than the rounds to either side of it. It has the additional crimp of a Shkas loading and the bullet appears very securely seated. It’s still live and there’s no obvious damage to the point indicating that the bullet has been pushed back into the case although I suspect that this is what has happened, despite the deep crimp. Before I pull the bullet and reseat it to it’s correct depth I thought I would ask just in case the round is intended to be short for some obscure reason. Can anybody advise please?
Jim


#2

The middle cartridge is the ShKAS ball round; it’s identified by the deep-seated 147 gr. bullet and the heavy neck crimping. Two possible–but not necessarily correct–explanations for the reduced overall length are to insure that the short bullet isn’t loosened in the loading cycle or, by increasing loading density, to increase the chamber pressure to the level of the heavier ShKAS loadings. The headstamp is possibly T 34 or T 35? At any rate, the bullet is just where it belongs. JG


#3

I’m glad I delayed deploying the bullet puller! Thank you very much for that - the headstamp is 38 E 39 by the way.
Jim


#4

The ShKAS round has no higher gas pressure so the reason must be another one. The deeper seating was only done on some lots, the majority got normal seatings.
The heavy crimp is indeed for a tighter fastening of the projectile since the kinetic stress on the cartridge during the feeding process was very high. For the same reason the ShKAS case had a thicker case wall and also a deeper seated primer which was ring crimped.


#5

Sectioned 7.62x54 #1 APT #2 AP #3 Shkas ball.

Sectioning done by Rob Sweet.

Steve


#6

What is the headstamp of the LPS round on the left with the purple casemouth seal?

There is not a whole lot of the “L” ball projectile sitting inside a normal case, slightly less than 1/2 of the case neck has projectile in it. Compare this to an API or APIT which completely fills the neck, you can see that there is not a whole lot of neck tension for the “L” ball. I imagine that the high cyclic rate of fire and reported “violent” action of the ShKAS would make short work of a cartridge with a loose projectile. I suspect that since not all ShKAS ball rounds have this seep seating and unusual crimp, that the particular lot or lots failed the “bullet pull” test and were sent back around for the extra work. Otherwise, the cartridge is unremarkable compared to a normal “L” ball round (ShKAS case of course).

AKMS


#7

AKMS,
The round with the purple casemouth seal is ‘188 63’.


#8

In +/-1963 Soviet small arms ammunition changed from unseal to sealed case mouth and primer. I cannot say as a rule, but I am under the impression that at first purple seals were applied before (already during the same headstamp year or the following) seals were red.