Originally Posted by LoboGunLeather

Standard infantry version of the M60 had an interesting feature I have not seen mentioned. On the left side of the receiver was a slot to hold the "assault bag" device, a reinforced canvas bag which contained a 100-round belt of ammo to feed directly into the weapon. This made the weapon somewhat more manageable while deployed on foot (patrol, ground assault, etc). No loose belt of ammunition that can become tangled up or inadvertently separate due to twisting.

Ammo for this device was routinely packed in 100-round belts laid in cardboard boxes, two boxes to each steel ammo can. The cardboard box could be inserted in the assault bag carrier, rip the box lid off, insert the end of the belt into the feed tray, close the breech cover, cycle the bolt, and ready to rock-n-roll again.

A sturdy padded sling was provided with the gun, supporting the weapon while carrying in a ready position and allowing the gunner to engage from a standing or crouch position, and either tucking the butt into the body (hip-shooting) or raising the weapon to shoot from the shoulder.

In Army infantry units each squad (generally a dozen troops) was assigned a M60, a designated machinegunner, and an assistant gunner. The assistant carried spare barrel(s) and a couple hundred rounds. All the other soldiers carried additional ammo for the M60 crew. All were trained and qualified with the weapon.

In fixed positions the 200-round belts were more commonly used. Single belt of 200 linked cartridges in a steel ammo can, open the lid and feed the belt into the weapon. The assistant gunner usually hand-fed the belt to prevent stoppages. The gunner could do the same thing while using the weapon on its integral bipod or resting on sandbags or similar positions. Technically a "crew-served" weapon, but a single soldier was capable of handling the weapon by himself.

Training and doctrine emphasized short controlled bursts of aimed fire (the goal was 3 to 5 rounds), with extended firing generally discouraged. Experienced gunners could easily fire single shots simply by controlling the trigger. Continual firing caused the weapon to heat up. I recall one incident in which a M60 became so hot that rounds were detonating as they chambered. A "runaway gun" was dangerous to everyone in the vicinity, especially the gunners, because rounds could detonate before being fully chambered with bursting cases causing shrapnel from the breech. The preferred method for dealing with such an event was to forcibly break the belt of cartridges, stopping the feed cycle.

On several incidents during night engagements I recall seeing machineguns with barrels glowing bright red from heat, quite visible from a considerable distance.

Another memory: Some of the M60 parts I saw in Vietnam were marked as made by Rock-O-La (the juke box company). That seemed appropriate because we commonly referred to automatic weapons use as "rock-n-roll".

Other markings I recall were Saco Defense and Maremont. As was the case with most military weapons, multiple contractors provided various parts and more than one maker might be involved in providing parts over the years of production.