The Kalashnikov SR1 semi-automatic rifle chambered for 223 Remington is the unique balanced-action rifle developed specifically for the IPSC practical shooting competitions.
Balanced recoil system
Balanced recoil system means that rifle features two gas pistons, entering single gas block above the barrel from opposite directions. Rear gas piston is attached to the bolt carrier group in a usual way. Forward gas piston, which moves opposite to the rear one, is attached to a sliding counterweight, located above the bolt carrier group. Both counter-recoiling masses are synchronized by a pair of rotating gears, so each discharge rearward and forward movement of the bolt group is balanced by a counter-moving mass attached to the forward gas piston, effectively canceling impulses generated by heavy reciprocating parts. As a result, rifle generates less felt recoil and is much easier to hold on target in rapid fire. The concept was developed in the AL-7 and AKB-1 Izhevsk-produced experimental rifles and then launched into series production as the SR-1 sports rifle.