Mini-gun

Machine Gun, High Rate, 7.62mm, M134
Dillon Aero's M134D-H (H for Hybrid) combines the titanium and skeletonized parts that were engineered for use in the M134D-T minigun with the steel housing of the previous M134D.
Type	Gatling-style machine gun
Place of origin	United States
Service history
In service	1963–present
Used by	See Users below
Production history
Designer	General Electric
Designed	1960
Manufacturer	General Electric, Dillon Aero, Garwood Industries, Profense
Produced	1962–present
Variants	See Design and variants below
Specifications
Weight	85 lb (39 kg) (41 lb (19 kg) lightweight mod.)
Length	801.6 mm (31.56 in)
Barrel length	558.8 mm (22.00 in)
Cartridge	7.62×51mm NATO
Caliber	7.62 mm (0.308 in)
Barrels	6
Action	Electrically driven rotary breech
Rate of fire	Variable, 2,000–6,000 rpm
Muzzle velocity	2,800 ft/s (853 m/s)
Maximum firing range	3,280 ft (1,000 m, 1,093 yd)
Feed system	Cartridge on disintegrating link belt or linkless feed; dependent on installation [500-5,000-round belt]
Sights	Dependent on installation; no fixed sights

The M134 Minigun is a 7.62×51mm NATO, six-barrel rotary machine gun with a high rate of fire (2,000 to 6,000 rounds per minute) which can also fire at a high sustained rate. It features Gatling-style rotating barrels with an external power source, normally an electric motor. The "Mini" in the name is in comparison to larger caliber designs that use a rotary barrel design, such as General Electric's earlier 20-millimeter M61 Vulcan, and "gun" for the use of rifle caliber bullets instead of shells used by an .

The Minigun is used by several branches of the U.S. military. Versions are designated M134 and XM196 by the United States Army, and GAU-2/A and GAU-17/A by the U.S. Air Force and U.S. Navy.

"Minigun" refers to a specific model of weapon that General Electric originally produced, but the term "minigun" has popularly come to refer to any externally powered rotary-style gun of rifle caliber. The term is sometimes used loosely to refer to guns of similar rates of fire and configuration regardless of power source and caliber.

The ancestor to the modern minigun was made in the 1860s. Richard Jordan Gatling replaced the hand-cranked mechanism of a rifle-caliber Gatling gun with an electric motor, a relatively new invention at the time. Even after Gatling slowed down the mechanism, the new electric-powered Gatling gun had a theoretical rate of fire of 3,000 rounds per minute, roughly three times the rate of a typical modern, single-barreled machine gun. Gatling's electric-powered design received U.S. Patent #502,185 on July 25, 1893. Despite Gatling's improvements, the Gatling gun fell into disuse after cheaper, lighter-weight, recoil and gas operated machine guns were invented; Gatling himself went bankrupt for a period.

During World War I, several German companies were working on externally powered guns for use in aircraft. Of those, the best-known today is perhaps the Fokker-Leimberger, an externally powered 12-barrel rotary gun using the 7.92×57mm Mauser round; it was claimed to be capable of firing over 7,000 rpm, but suffered from frequent cartridge-case ruptures due to its "nutcracker", rotary split-breech design, which is fairly different from that of a Gatling. None of these German guns went into production during the war, although a competing Siemens prototype (possibly using a different action) which was tried on the Western Front scored a victory in aerial combat. The British also experimented with this type of split-breech during the 1950s, but they were also unsuccessful.