9×21 SP-10 SP-11 SP-12

The development of this relatively high-powered pistol ammunition, intended for both sub-machine guns and semi-automatic pistols, commenced in Russia during the early nineties. The key goal was to provide military and law enforcement personnel with pistol ammunition, which would be, more effective against body armor than available rounds. Designers from TSNII TochMash (city of Klimovsk, Russia) first developed an armour piercing bullet with hardened steel core, exposed at the tip of the projectile, and then developed a new experimental round, initially known as RG052. Since 1993 this development was funded by the FSB (Federal Security Service of Russia), and the first production rounds were issued under the codename SP-10 (SP stand for Spetsialnyj Patron – special cartridge). Adopted in 1996, SP-10 ammunition is almost entirely used in one line of pistols (known under the codenames SR.1, Vector or SPS) and in one sub-machine gun, the SR.2 Veresk, both used by FSB and special elements of other law enforcement agencies in Russia. The original armor piercing SP-10 cartridges were soon complemented by other types of ammunition, including the SP-11 with a low-ricochet ball bullet (suitable for use against unprotected targets and for training), the SP-12 with expanding bullet and the SP-13 with armor-piercing tracer bullet. In about 2003 this nomenclature was changed to the Russian standard 7Nxx designations, marking the official approval of this ammunition for all services.

The SP-10 cartridge, currently known as the 9×21 7N29, has a straight rimless case, usually made of steel and with dark green lacquer coating. The armor-piercing bullet is of proprietary design; it has a hardened steel penetrator core that is exposed at the bullet tip, to ease the separation of the jacket upon the penetration of body-armor plates. The space between the penetrator and jacket is filled with polyethylene. The bullet is designed to stay intact upon impact with soft body tissue to conform to international treaties, and in this case it acts as a typical “ball” bullet of similar weight and energy. It must be noted that this cartridge is ballistically similar to some of the “hotter” 9×19 loadings; the longer case is necessary because of the longer bullet, which has relatively low volume density because of its composite core that consists of polyethylene filler and relatively long steel penetrator of 6mm diameter. Other types of bullets are fairly conventional.

These cartridges must never be used in pistols chambered for commercial 9×21 IMI ammunition because they generate pressures far beyond industry standards for the 9×21 IMI.

Designation

Manufacturer

Bullet weight, g

Muzzle velocity, m/s

Muzzle energy, J

Comments

RG052

Russia

6,5 – 7

415 – 430

560

Original experimental loading, 1992

7N28 / SP-11

Russia

7,9

390

600

With low ricochet FMJ bullet

7N29 / SP-10

Russia

6,7

410

563

With AP bullet

7BTZ

Russia

7,2

395

562

With AP-T (tracer) bullet