MBA Gyrojet
From Gunpedia
The Gyrojets were a family of unique firearms developed in the 1960s named for the method of gyroscopically stabilizing its projectiles. Firing small rockets rather than inert bullets, they had little recoil and didn't require a heavy barrel to resist the pressure of the combustion gases. The result was a very lightweight weapon with excellent ballistics. Long out of production, today they are a coveted collector's item with prices for even the most common model ranging above $1,000. They are, however, rarely fired; ammunition, when available at all, can cost over $100 per round.
[edit] History
Robert Mainhardt and Art Biehl joined forces to form MB Associates, or MBA, in order to develop Biehl's armor-piercing rocket rounds. Originally developed in a 13 mm caliber, the cartridges were self-contained self-propelled rockets.
A family of Gyrojet weapons was designed, including a pistol, carbine, "rifle" and squad-level light machine gun. However only the pistol and carbine were built. The space age-looking carbine versions were tested by the Army, where they proved to have problems. One issue was that the vent ports allowed the humid air into fuel, where it made the combustion considerably less reliable. The ports themselves could also become fouled fairly easily, although it was suggested that this could be solved by sealing the magazines or ports.
Aside from a few Gyrojets tested by the United States Military, most Gyrojets were sold on the commercial market starting in the mid-1960s. These were Mark I Gyrojets, which launched a .51 caliber rocket, and ammunition was costly to produce and buy. In 1968, the Gun Control Act of 1968 created a new legal term, the destructive device. Under the new law, any weapon firing an explosive-filled projectile over a half-inch in diameter was considered a destructive device and required paying a tax and obtaining a license. The registration process was changed several years later, but in the interim, MBA created the legal Gyrojet Mark II, firing a .49 caliber rocket.
