Fallows, James. "The American Army and the M-16 Rifle". In The Social Shaping of Technology (2nd ed.), edited by Donald MacKenzie and Judy Wajcman, 382-394. Buckingham: Open University Press, 1999.

Fallows, James. "The American Army and the M-16 Rifle". In The Social Shaping of Technology (2nd ed.), edited by Donald MacKenzie and Judy Wajcman, 382-394. Buckingham: Open University Press, 1999.

• American soldiers in Vietnam were issued the M-16 rifle, a modified version of the AR-15 rifle developed by Armalite. Unlike the deadly and reliable commercial variant, the M-16 had issues with jamming and misfiring that contributed to American combat losses. This was because of modifications made to the AR-15 by the Army for generally inane and petty reasons relating to internal politics (382).
• The issues with the M-16 were severe enough that, after receiving many letters from angry parents, Representative Richard Ichord [D-MO] was placed at the head of a congressional committee investigating the issuance of the rifle (382). 
• In the late 19th Century, European weapons designers discovered that smaller calibre bullets caused disproportionate damage to flesh compared to larger calibres because smaller rounds had a less stable flight and distributed damage for widely. This revelation was utilized by US General Willard Wyman to switch US Army standard calibre from .30 to the smaller .22 rounds (383).
• This was the subject of massive fights within the US Army and the NATO alliance. In the 1950s, the European members of NATO advocated adopting a smaller calibre, although the US managed to impose the larger .30 calibre as standard (385).
• In his studies of American combat units in WWII, Samuel Lyman Atwood Marshall, an Army combat historian, found that around 80% of soldiers never fired their weapons in combat. The exception to this was those troops issued Browning automatic rifles, who were almost always the first to open fire due to the confidence in their fully automatic weapons. (383-384).
• In response to demands for a transition to a fully automatic weapon, the US Army adopted the M-14 rifle, a lighter and fully automatic version of the M-1 rifle, the previous service weapon. This weapon had major drawbacks, namely that its lighter build made it unsuitable for fully automatic fire; sometimes the gun splintered, or injured the user, or was difficult to aim with. Nevertheless, the M-14 was adopted in 1957 and used until the mid-1960s  (384).
• The M-14 was approved partially because the Army Materiel Command and associated private contractors -- collectively known as the ordinance corps -- tested rifles based on controlled fire at set distances. The ordinance corps used this testing method, as opposed to the suitability of weapons in close-range combat, because it appealed their values of marksmanship, standardization, and an emphasis on using fewer rounds, thus putting less pressure on the ammunition supply chain that they were responsible for (384-385).
• Eugene Stoner developed the AR-15 while working for the Armalite corporation in 1957. The rifle was lighter than the M-14, allowing soldiers to carry more ammunition, but used smaller .22 calibre rounds so the kickback was manageable and the rifle was still accurate during automatic fire. The AR-15 was extremely reliable and almost never jammed even during automatic firing. Moreover, the use of a plastic stock and mass produced parts meant that the AR-15 was much less expensive than other rifles (385-386).
• During testing by DARPA, the AR-15 received high praise for being a better rifle than the M-14, cheaper and easier to produce, easier to maintain under difficult conditions, and simpler to train with. The ordinance corps dissented from this opinion, arguing that the poor range of the AR-15 meant that the US should stick with the M-14 (386).
• The rejection of the AR-15, despite its use by special forces units in Vietnam, prompted an investigation by Secretary of the Army Cyrus Vance, who discovered that the ordinance corps had rigged tests in favor of the M-14 through a widespread conspiracy that involved using sup-par guns and ammunition as well as using publishing test results that reflected poorly on the AR-15 (386-387).
• In 1963, with support from President Kennedy and Secretary of Defense Robert McNamara, Army special forces and airborne units, as well as CIA operatives and Air Force soldiers, received permission to use the AR-15 in Vietnam (386).
• The increased usage of the AR-15 by Army special forces and the Air Force in 1963 led Secretary McNamara to centralize production and distribution of the weapon with the Army Materiel Command. The ordinance corps responded to this by using their power to modify the AR-15 to fit their desires, producing the M-16 (387).
• The first modification was the addition of a manual bolt closure, by which a soldier could manually insert a cartridge that had jammed or had not seated itself. The Marine Corps and Air Force were strongly opposed to this change, as the AR-15 had no history of jamming that would justify the addition and the modification increase weight, cost, and complexity. The change had been ordered by the Chief of Army Staff, General Earle Wheeler (387).
• The 'twist' of the rifle barrel was increased from one rifling turn per 14 inches to one turn per 12 inches, thus making the bullet spin faster and increasing stability. This also reduced the benefits of an unstable flight derived from the smaller calibre rounds. This change was justified on the basis that the AR-15 had originally been unable to meet army standardization testing at -65 degrees Fahrenheit, although this testing was likely rigged (387-388).
• The gunpowder used in the rifle was switched to 'ball powder' in 1964.  Different types of gunpowder explode at different rates, affecting multiple aspects of gun design. The AR-15 fired using the 'improved military rifle' powder, but the ordinance corps found that this produces a bullet that was too slow for their technical standards -- despite the success of this slower bullet in combat in Vietnam. Unlike improved military rifle powder, ball powder causes a build-up in residue that can cause the gun to jam. This change in powder type transformed from the rifle from one that essentially never jammed, to one that jammed on over half of firing tests (388-390).
• Repeated tests, from 1964 onwards, showed that the M-16 -- although better than the M-14 -- was an unreliable weapon prone to breakdowns and jamming and that the reason for these malfunctions is the use of ball powder as opposed to improve military rifle powder. Despite this, the M-16 remained in use with ball powder (389-390).
• In 1964, the Colt company conspired with members of the Army Materiel Command to have the M-16 pass basic standardization tests, which it kept failing, by allowing them to use improved military rifle powder to pass the tests. The Army Materiel Command then continued to issue rifles solely using ball powder, supplied by Colt, despite this powder never passing the tests (391).
• When regular American soldiers were first deployed to Vietnam in 1965, there were issued the M-14 rifle. Upon deployment, US soldiers discovered that the M-14 was inaccurate in automatic fire and much preferred the AK-47 used by the Vietcong or the AR-15 used by the special forces (390).
• Seeing the advantages of the AR-15, William Westmoreland, the Commander of American forces in Vietnam, requested that the M-16 be issued as the standard rifle to American soldiers in Vietnam. The ordinance corps approved this request, but refused to replace the M-14 as the Army standard or supply General Westmoreland with M-16s issued with anything except ball powder (390-391).
• The ordinance corps continually refused to respond to complaints about the M-16, using these grievences as evidence that they had been right about the AR-15/M-16 all along. Army command redirected to blame on soldiers failing to maintain their weapons properly, although this was frequently impossible due to a lack of cleaning supplies available for the rifle (391).