Weapons designed for underwater use by frogmen have been in the inventories of major armies for some years, but are not publicized, and the first such weapon to be seen at an international arms exhibition was the Russian 4.5 mm Underwater pistol SPP-1, first shown in 1992. Conventional firearms do not perform well underwater, for various technical reasons, and thus the design of this pistol is quite unlike any weapon used on land.
The Underwater pistol SPP-1 have four barrels, arranged in a block so that they can be tipped down to expose the breech end for loading. The round of ammunition is a drag-stabilized dart 115 mm long, the rear end being secured inside a cartridge case of fairly conventional shape. Four rounds are held together by a clip so that the whole clip can be handled as one unit and the four rounds slipped into the four barrels.
The barrels are then folded down and locked to the breech, which contains a self-cocking firing mechanism which fires each round in succession for four pulls of the trigger. The cartridge contains a piston which, when the powder explodes, is driven forward and launches the dart from the barrel; the piston is stopped by the bottle-neck of the cartridge so that no gas escapes into the water.
The darts are sufficiently accurate to strike within a 150 mm (6 in) circle at 100 meters range when fired in the air and the short-range underwater accuracy is said to be comparable. The effective underwater range varies according to the depth and water pressure; at five meters depth, the dart has a lethal effect at a 17 meters range, while at 40 meters depth the effective range is only six meters.
At these ranges, the darts are capable of penetrating all types of wet or drysuit, face-masks, and helmets. And, of course, they can be used as self-protection against the more dangerous types of fish and mammals liable to be encountered during underwater activities.
The Russians have also developed a 5.66 mm underwater rifle using a dart cartridge. With approximately double the range of the pistol, it is a semi-automatic weapon that uses a similar mechanism to the Kalashnikov rifle.
Technical specifications: 4.5 mm Underwater Pistol SPP-1
|Manufacturer:||Russian state arsenals|
|Caliber:||4.5 mm Special|
|Barrel:||about 8.25 in (210 mm)|
|Weight (empty):||33.5 oz (995 grams)|
|Magazine capacity:||4 rounds|