The MK19 is an “air cooled, blowback operated machine gun, with five major assemblies.” It uses 40mm ammunition that is belt-fed through the left side of the weapon by a disintegrating, metallic link belt. Some of its highlight capabilities is its very transportable, has a nice maximum range of 2,212-m, a cyclic rate of fire of 325-375 RPM, its barrel does NOT overheat and is relatively light at 75.6 lbs. The “blowback” or recoil of the weapon (500 lbs worth of force) is what allows it to fire.
Ammunition for the MK19 supports almost every mission it was designed to support. Both 40-mm rounds have their own, special capabilities that are extremely important to ground troops. The M430 HEDP has a casualty radius of about 15 meters and can penetrate 2 inches of steel. The M383 HE also has a kill radius of about 15 meters.
Primary uses for the MK19 revolve around its ability to give a heavy volume of close, accurate and continuous fire. Such missions include, but are certainly not limited to protection of motor movements, defending against hovering aircraft, destroying lightly armored vehicles, high volumes of fire in a wide engagement area, cover of obstacles and indirect fire from defilade positions.
Although the MK19 is a recent entry into the Army’s machine arsenal, its development began in 1963. The first version was a hand-cranked, multiple grenade launcher called the MK18. In 1966, the need for more firepower inspired the development of a self-powered 40mm machine gun called the MK19 MOD 0. This model was neither reliable enough nor safe enough for use as a military gun. With improvements beginning in 1971 the MOD1 was introduced which performed effectively in Navy reverie patrol crafts. This was the birth of the MK19 as broader applications for its use were found. In 1973, the Navy developed the MOD2, which featured improved reliability, safety and maintainability. In 1976, a complete redesign resulted in the MK 9 MOD 3, which the Army took ahold of in 1983.
As long as the Army’s Infantry and ground forces have a need for heavy volume of close, accurate and continuous fire, the MK19 can be expected to be one of the primary weapons of choice for the foreseeable future.