The Right Arm of Democracy
The M-16 was the staple of United States diplomacy in Vietnam. It is a gas operated, selective fire rifle that fed from a detachable 20-round magazine that fired a 5.56 cartridge. The rifle was created by Eugene Stoner and James Sullivan of Armalite Inc. in the early 1950s. The U.S. government had been looking desperately to replace a majority of their arsenal at the same time. The rifle was offered up for U.S. Army Infantry trials at Fort Benning, Georgia thereafter. It was not approved by the Army but did strike the interest of the Air Force. It was then given the designation AR-15 (a name we commonly see thrown around today) and began production in 1961. By the mid-1960s, the Army had adopted it as a replacement for the M-14. In 1961, Colt took over the patent rights and was the sole producer of the rifle for a number of years. The rifle then saw transformation into the M16A1, which is the one most people are familiar with.
The M16A1 is a gas operated rifle which featured an upgrade: selective fire. The previous model was only semi-automatic. This upgraded version was virtually identical; it was made from the same material, fired the same round, fed from the same 20 round magazine. However, it did feature a burst fire option- three round burst- and a plunger assist to help return the bolt home in case of failure to fire. The rifle weighed just under eight pounds, composed primarily of aluminum alloy and plastic although the bolt and receiver were made of steel. This made the rifle incredibly light and easy to maneuver. Another recognizable feature of the M-16 is its carrying handle. This feature was added to incorporate the rear sights as well as offer a simple carrying device. The rifle featured in-line recoil, meaning that when firing the rifle fired in a straight line which reduced the chance of dancing off target. The rifle also bragged about being self-cleaning which would come to haunt Colt and its investors later.
The M-16's initial combat baptism was in Vietnam. By 1966, it had been issued to almost every frontline soldier including ARVN troops. There is a mythos that goes along with the M-16 service history in Vietnam that I would like to dispute. Many veterans and historians criticize the M-16 for its unreliability in country. It often jammed when operated at peak efficency and was very complicated to take apart compared to its counterpart, the AK. Since then, the rifle has seen ridicule because of the initial trials and usage in Vietnam. What those historians and veterans do not tell you (or do not know) is that the fault behind the M-16's functionality is more complicated than that. Going back to the so called "self-cleaning" feature, this simply was not true. It did needed to be cleaned and quite frequently due to its direct impingement gas system that produced a lot of carbon buildup and fouling in the rifle. No cleaning kits were issued with the rifles which further exacerbated the issue. A lot of people liken this to the AK system which does not require much cleaning (or does not see any cleaning at all in some circumstances), making the M-16 seem like the worse rifle of the two. Also, the powder charge was changed prior to shipment off to Vietnam. The rifle was tested and approved with DuPont IMR8208M powder but was switched to Olin Mathieson WC846 powder which produced the major fouling issue. The M-16 initially (prior to the M16A1) featured no forward assist to help in case of jams, which rendured the rifle useless in situations where it jammed. The chrome plated chamber also featured some corrosion resulting from misfires. A Congressional investigation was implemented and found these as the main causes as to why the rifle performed so poorly in Vietnam. Once the M16A1 was introduced, these problems went away and by 1968 the rifle lost the majority of the mythos that had plauged it from the start.
Since the rifle was very lightweight, it received the derrogatory nickname "The Mattel Gun" because of its almost plastic-like composure. After Vietnam, it has been modified into its current pattern, the M4A1 and the M16A4, which is used by the U.S. military to this day. Many other nations have also adopted some variant of the M-16 in their own militaries as well including Japan, Greece, Estonia, and more.