The M60 Machine Gun has been the US Army's general purpose machine gun since 1950. It fires the standard NATO 7.62 mm round and is used as a general support crew-served weapon. It has a removable barrel which can be easily changed to prevent overheating. The weapon has an integral, folding bipod and can also be mounted on a folding tripod. 

Length: 42.4 inches (107.70 centimeters)
Weight: 18.75 pounds (8.51 kilograms)
Bore diameter: 7.62mm (.308 inches)
Maximum effective range: 3609.1 feet (1100 meters)
Maximum range: 2.3 miles (3725 meters)
Muzzle velocity: 2800 feet (853 meters) per second
Rates of fire:
Cyclic: 550 rounds per minute
Rapid: 100 rounds per minute*
Sustained: 100 rounds per minute*
(* with barrel changes at each 100 rounds)
Unit Replacement Cost: $6,000

The M60E3 7.62mm machine gun is a lightweight, air-cooled, disintegrating metallic link-belt fed, portable or tripod mounted machine gun designed for ground operations like its predecessor, the M60. It is gas operated with fixed headspace and timing which permits rapid changing of barrels. (Associated components: mount, tripod, machine gun, 7.62mm, M122). Slightly different from its "parent," the M60, the M60E3 has a receiver-attached bipod which easily deploys for stability. It has an ambidextrous safety, universal sling attachments, a carrying handle on the barrel, and a simplified gas system that does not require safety wire to prevent loosening. However, the light weight barrel is not safe for overhead fire and is not capable of sustaining a rapid rate of fire of 200 rounds per minute without catastrophic failure of the barrel. 

The M60E3 (light weight version of the parent M60) was fielded with the intention to reduce the load carried by the gunner. However, the reduction in weight resulted in firing limitations and a loss of reliability that severely restricts the use of the weapon in the Fleet Marine Force. Consequently, troop acceptance of the E3 has been very poor. This gun will be replaced by the M240G.