SR-3 "Vikhr" compact assault rifle (Russia) 

Caliber: 9x39 mm 
Action: Gas operated, rotating bolt
Overall length: 610 mm with open buttstock; 360 mm with closed buttstock 
Barrel length: ?? 
Weight: 2.0 kg empty 
Rate of fire: 900 rounds per minute 
Magazine capacity: 10 or 20 rounds 

The SR-3 "Vikhr" ("Whirlwind") compact assault rifle was developed in TSNIITOCHMASH by A. Borisov and V. Levchenko. Initially known as "MA" (Malogabaritnyj Avtomat = small-size assault rifle), it was based on the silenced 9 mm AS "Val" assault rifle, and intended for concealed carry by special VIP protection teams and State security operatives. The SR-3 is widely used by various FSO (Federal Protection Service, a VIP protection organization, which guards the President and the government of the Russian Federation) and FSB (Federal Security Service) operatives, elite Russian counter-terror teams and other specialized users in the MVD and Russian police. In terms of size and weight, the SR-3 is similar to most submachine guns, but it fires much more powerful 9x39mm ammunition, available in armor piercing (SP-6) and ball (SP-5) loadings. Thus, SR-3 is considered as an assault rifle rather than a submachine gun.

The SR-3 features the receiver, machined from a bar of steel, and gas-operated action with long stroke piston, plus the same rotating bolt group from the AS. However, the SR-3 has no integral silencer, nor provision to mount one, and thus is much shorter than the AS. Other changes included a more compact, top-folding butt and simplified flip-up rear sight. The redesigned charging handle, made in the form of dual sliders above the forearm, must be grasped by thumb and index finger and then retracted to load the weapon. The trigger unit is generally the same as in the AS, but the AK-type safety is replaced by ambidextrous lever above the pistol grip. The fire mode selector is of cross-bolt, push button type and located behind the trigger, inside the trigger guard. SR-3 uses same polymer magazines for 10 or 20 rounds, as the parent AS and VSS rifles. 

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