9x39mm

From Wikipedia, the free encyclopedia

The 9x39mm cartridge is a subsonic rifle round used in Russian firearms. It was based on the 7.62x39mm M43 cartridge, but with the neck opened up to accommodate a 9 mm bullet. The intent was to create a subsonic cartridge for suppressed firearms of special forces with more power, range and penetration than handgun cartridges, as 5,45x39 mm cartridge introduced in 1974 for AK-74 lacks bullet weight for acceptable energy at subsonic velocities (although there is subsonic load for it). The bullet is heavy, approximately 16 grams, double that of the 7.62x39mm, and is subsonic, avoiding the sound of a sonic boom. The low velocity limits the effective range in comparison with standard non-suppressed assault rifle, but when comparing with handgun rounds commonly fired by SMGs, 9x39 mm round has almost twice the energy of subsonic 9x19 mm round and a bullet with higher BC an sectional density, thus having effective range of about 300 - up to 400 m.

There are 3 versions of the 9x39 mm cartridge: the SP-5, the SP-6, and the PAB-9. The SP-5 was developed by Nikolai Zabelin. It is a conventional lead core FMJ bullet, but developed for accuracy. The SP-6 was developed by Yuri Folov. It has a dense metal core (not covered by jacket at the tip), designed to be armor piercing. It can penetrate 2 mm of steel at 500 meters or 6 mm of steel, 2.8 mm of titanium or 30 layers of Kevlar at 200 meters. At 100 meters it penetrates 8 mm of steel, containing enough power to neutralize the soft target behind. The SP-6 bullet is expensive, so an attempt was made to make a lower cost version, the PAB-9, but it sacrificed too much performance to be usable.

The weapons that use the 9x39mm cartridge include the AS Val, AK-9, OC-11 Tiss and OC-14 Groza assault rifles, the SR-3 Vikhr and 9A-91, and the VSS Vintorez and VSK-94 sniper rifles.