HK P11

Since ordinary-shaped rounds are inaccurate and have a very short range when used underwater, this pistol fires steel darts about 10 centimeters (3.9 in) long. It has five barrels, each of which is loaded with a cartridge, giving the gun a pepper-box appearance, and it is electrically ignited from a battery pack in the pistol grip. After firing all five cartridges, the barrel unit must be sent back to its manufacturer for reloading. It is very similar to its predecessor, the Mk 1 Underwater Defense Gun. In the past, Heckler & Koch has denied knowledge of its existence.

Specifications
Weight	1,200 grams (42 oz) loaded Battery pack 700 grams (25 oz)
Length	200 millimetres (7.9 in)
Width	60 millimetres (2.4 in)
Cartridge	7.62 x 36 mm, about 100 millimetres (3.9 in) long, miniature solid-fuelled rocket with fins
Caliber	7.62 mm
Action	Electric actuated
Effective range	30 metres (98 ft) in air, 10 to 15 metres (33 to 49 ft) underwater
Feed system	5 rounds, each in a barrel
Sights	14.6 centimetres (5.7 in) between sights

 

FULL HK P11 SPECS HERE