The 5.66 mm APS underwater assault rifle is a selective-fire, gas-operated rifle. The firing mechanism is reported to be generally based in the Kalashnikov rotating bolt system. Were it not for the extremely large magazine, it would look a lot like an AKM assault rifle with a folding stock. The projectile is a dart, drag stabilized, which is held in a cartridge that appears to be based on the 5.56 x 45 mm NATO cartridge. Each dart is 120 mm long, the entire round is 150 mm long. This accounts for the oversized magazine, which appears to be made of clear plastic. Each cartridge weighs 26 g. The effective range in air is given as 100 m. The underwater range is 30 m at 5 m depth, and 11 m at 40 m depth. It is reported that at these ranges, the dart is capable of inflicting fatal wounds through the normal types of underwater suits and through 5 mm of glass, e.g. a face mask.
Cartridge: 5.66 mm Model MPS
Operation: gas, selective fire
Feed: 26-round box magazine
Weight: 2.4 kg empty, 2.7 kg with empty magazine, 3.4 kg loaded
Length: 840 mm butt extended; 614 mm butt folded
Height: 187 mm
Width: 65 mm
Manufacturer: Institute of Precise Mechanical Engineering, Izhevsk,
Russia
Status: In production; offered for export sales
Service: Russian Special Forces