Second Chechen War[citation needed] 2008 South Ossetia war[citation needed] The PP-19 Bizon (Russian: Пистолет Пулемёт Бизон, Pistolet Pulemyot Bizon, Pistol Submachine Gun "Bison") is a 9×18mm Makarov submachine gun developed in 1993 by the Russian company Izhmash.

[2][3][4] The Bizon was developed at the request of the Russian Ministry of Internal Affairs (MVD)[4] and is primarily intended for counter-terrorist and law enforcement units that need fast and accurate fire at close ranges.

The Bizon is issued to armed response units of the Federal Security Service (FSB) and Ministry of Justice in Russia.

[citation needed] The Bizon uses a simple straight blowback method of operation; an unlocked breech system reduces cost and build complexity.

[3] The Bizon's operating cycle is characterized by a very short recoil stroke; standard 9×18mm ammunition will only drive the bolt partially to the rear of the receiver and results in a cyclic rate of 680 rounds per minute.

Due to the slow cyclic rate, it has the effect of reducing perceived recoil and increasing firing stability and hit probability.

[1] The pinned and riveted sheet metal receiver of the Bizon is derived from the AKS-74 and has been modified at the front end, since the gas system was omitted.

[6] An original five-piece anti-bounce device is built into the trigger unit and this functions as a rate reducer, delaying firing until the bolt has settled entirely into battery.

These are selected by the operator depending on the weapon's tactical employment and include sound suppressors, muzzle brakes, compensators, and flash hiders.

The Vityaz-SN is chambered in 9×19mm Parabellum, it entered Russian service in 2005, and continues to be the country's standard issue submachine gun for all military and police forces.

It features the AK-19 folding telescopic buttstock, ambidextrous fire selector controls, an optional quick-detachable sound and flash suppressor, a Picatinny rail mounted on the dust cover for various optical sights, an improved handguard design with an M-LOK interface on the sides and slots for Picatinny rails on the top and bottom, and a lighter weight design.