The Chinese firm (Chongqing Jianshe Industry Group) that supplies CS/LM12 six barrel 7.62 machine-guns to the Chinese Army is now offering the weapon to police organizations. The United States first introduced this multi-barrel machine-gun design fifty years ago, for use in jet fighters and firing 20mm rounds. Also called the "Gatling Gun", after the original 1860s version that was hand cranked, the 1960s version required electrical power to spin the barrels.
The basic design was soon adapted to fire 7.62mm bullets and used on helicopters or ground vehicles. China began building similar weapons in the 1990s, and now uses some of these 7.62mm weapons with elite infantry units.
The latest version of this weapon is the U.S. Air Force GAU-2B. This is a remote control turret using a six-barrel 7.62mm machine-gun. This system has a rate of fire of 3,000 rounds per minute (50 per second) and max range of 1,500 meters. The system weighs 363 kg (800 pounds), including 4,000 rounds of ammo. A member of the aircraft crew uses a video game like interface to operate the gun.
The Chinese CS/LM12 has adjustable rates of fire (2,500 to 6,000 rounds a minute). The original GAU-2 (called M134 by the U.S. Army) was built to handle 6,000 rounds per minute rate, but it was found that 4,000 rounds a minute was adequate and used available ammo more efficiently.