Any Advantage of 7.62x39 Small Primer Brass vs Large Primer Brass?

[MSR_Gal]

Now that Hornady is making small primer 7.62x39 brass, is there an advantage in accuracy and/or pressure tolerance versus large primer brass?

My rifle is a CZ 527 with custom (McGowen) varmint weight barrel: 1:16 twist, .303 bore, .311 groove, and Match (Lapua) chamber in an HS Precision PSV091 stock.

 

[Sniper338]

Prolly alittle pressure gain. Wont know accuracy till you try it and see if you can tell prolly. Being it a small case Id go with small if I was in your shoes.

 

[rkittine]

In my .308s I now use Palma brass for the supposed improvement in pressure handling with the small primer, but I an a newbie at this.

Bob

 

[TAJ45]

A simple matter of more material to move via pressure. A small primer will definitely allow higher pressure. Some have feel that cold weather ignition can be compromised, others have not had that problem. I haven't read of any serious tests in that area - anyone?

 

[2506]

Not about cases but a heads up on new bullet from Nosler. They are coming out with a 123 Ballistic Tip for the 7.62x39.

 

[rkittine]

I too have heard about the ignition issue also, but in my limited experience have not seen anything I think is causing fluctuations.

Bob

 

[people]

Accuracy depends. Only your rifle will tell you what it likes. Going from LR to SR primers I have not really noticed any problems in the winter with one exception. I have a popgun load for frangible bullets. With SR and one type of powder it does not like going off. Everything else goes off just fine. Granted I have not tested every powder and primer combination.

 

[243winxb]

http://forum.accurateshooter.com/threads/flash-hole-size.3966076/

Spit-Hole Effects on the Ballistics of a 7.62-mm Cartridge.

See at link.

 

[jds holler]

I've got an old batch of Remington small primer brass that I save for use in my "bench rest SKS". I've been able to achieve 2 MOA with my best loads. Can't say if the small primer pockets are responsible for the amazing accuracy, but case life seem good. jd

 

[243winxb]

"bench rest SKS"

 

[jds holler]

 

[2506]

Give your rifle a case full of H322 29 grs in a Lapua case Rem 9 1/2 primer with a 123 Hornady Soft Point bullet and see what accuracy you get. My YUGO SKS's really shoot this load very accurate. I use a Lee Factory Crimp die to help hold this bullet in the case.