SPP-1 underwater pistol (Russia)
Type: Double Action Only
Weight: 950 g empty
Length: 244 mm
Barrel length: 203 mm
Capacity: 4 rounds in separate barrels
The SPP-1 (Spetsialnyj Podvodnyj Pistolet = Special Underwater Pistol) has been developed in late 1960s by the TSNIITOCHMASH organization on request from the Soviet Navy. The SPP-1 was intended for Soviet combat divers ("frogmen"). Later the SPP-1 has been modified to SPP-1M, with several internal upgrades, and is still used by Russian Navy special forces, as well as offered for export through Russian Governments' military sales organization, RosOboronExport.
SPP-1 is a non-automatic, manually operated handgun with four barrels. Barrels are hinged to the frame in the same manner as on break-open shotguns. For reloading, barrel cluster is tipped to expose chambers, and four cartridges are inserted into barrels. To speed up ejection and reloading cycle, cartridges are loaded using flat clips, made from steel. The double-action trigger unit consists of a striker, mounting on a rotating base, so during the each trigger pull the striker is cocked and simultaneously rotated to the next, unfired barrel. The single lever, located at the left side of the frame, controls the safety and reloading. It has three positions, top for "Reloading" (barrel release), middle for "Safe" and bottom for "Fire".
To be effective underwater, SPP-1 uses special proprietary ammunition, with rimmed bottlenecked cases 40mm long, sealed from water. Unusually long bullets are made from mild steel, and are drag-stabilized underwater; on air, bullets are not stabilized at all, so the effective range "above the air" is limited, but the "lethality range" is about 15 to 20 meters. When underwater, lethality range degrades with the increase of the depth: at 5 meters depth, the effective range is about 17 meters; at 20 meters depth, the effective range is only about 11 meters.