MBA Associates Mark I Gyrojet Pistol Model B

The MBA Associates founded by nuclear scientist Robert Maynard and arms designer Arthur Bill was making Gyrojet pistol between 1962 and 1970 in San Ramon, California. The Gyrojet weapon was one of the rare attempts to develop an entirely different weapon with some unique properties. This weapon tried to achieve several goals, including the low noise of firing and underwater fire capabilities, along with significant firepower and penetration. In doing so, it was far from any conventional firearms; in fact, it was a hand-held, multi-shot rocket launcher that fired "armor piercing" projectiles, made from steel and with pointed nose. Each projectile contained its own rocket engine and means for stabilization - either in the form of retractable fins or in the form of inclined jet nozzles which forced the missile to rotate, and thus provide gyroscopic effect for stabilization. Each rocket "motor" burned for about one tenth of a second; maximum velocity of about 380 meters per second (1250 fps) was achieved at ranges about 20 meters from muzzle, while muzzle velocity was as low as 30 meters per second (100 fps). Because of that slow acceleration the Gyrojet was almost useless a weapon at short ranges, within 5-7 meters, gaining its full power only at ranges of about 40-60 meters (yards). Major difference between Mark 1 and Mark 2 weapons was caliber of projectiles – original Mark 1 weapons used 13mm rockets, while later Mark 2 weapons used 12mm rockets to conform with US gun laws that set maximum legitimate caliber for civilian weapons as 0.5 inch (12.7mm). Gyrojet ammunition today is very expensive and can cost oup to $100 per round.