Just over nine months later, on Oct. 12, 1962, the Secretary of Defense sent a memorandum to the Secretary of the Army, requesting that the Army conduct a comparative evaluation of the M14, AR15, and then-Soviet AK47 rifles. That evaluation was conducted in late 1962 with a recommendation report submitted to the Secretary of the Army in mid-January 1963.

“In the review of the report, the M14 was shown as superior to the AR15 in penetration, night firing, and reliability, and the AR15 superior to the M14 in automatic fire and transportability,” the history reads. “In all other military characteristics, both weapons met or exceeded the military requirements.”

“In the review of the report, the M14 was shown as superior to the AR15 in penetration, night firing, and reliability, and the AR15 superior to the M14 in automatic fire and transportability,” the history reads. “In all other military characteristics, both weapons met or exceeded the military requirements.”

The Army report also acknowledged the political factors and pointed to the importance of the NATO agreement on ammunition standardization.

After considering all relative merits, Army Chief of Staff recommendations ranged from a proposed FY 64 Army procurement of 50,000 to 100,000 AR15 rifles “and in priority, use them to equip Air Assault units, Special Forces units, and Airborne units” to the FY 64 procurement of “a sufficient number of the M14 (M) Modified rifles to provide an automatic rifle capability to all infantry squads armed with the M14 rifle.”

These and other recommendations were approved by both the Secretary of the Army and Secretary of Defense.

On March 11, 1963, the Secretary of Defense designated the Army to be “the Department of Defense agent for procurement of the AR15 (M16) system for all services.”

The guidance further specified that “beginning with the FY 64 procurement, only one rifle, rather than separate service versions, is [to be] produced and that it is [to be] produced with minimum delay [and that] modifications of the weapon and its ammunition are to be concurred in by all four services.”

Nine months later, on Dec. 11, 1963, the Army designated the AR15 as the M16 rifle.

The Army procurement had actually begun with the purchase of a small quantity (338 rifles) of AR15s for test and evaluation in FY 62, followed by another limited procurement, one-time buy of 85,000 rifles in FY 64.

While noting that no further procurement was initially anticipated, the Army’s 1968 history added that “an urgent requirement for the rifle in Vietnam in 1965 set the stage for a large purchase [327,405 rifles] in FY 1966. Subsequent procurements in FY 1968 and FY 1969 have been based on production capacities rather than on any well-defined, long-range program.”

Unfortunately, after the first few months of tactical employment, in the fall of 1966, U.S. Army units in Vietnam began to report “excessive stoppages and malfunctions” with their new rifles. Preliminary investigations of these reports pointed to a lack of proper training and maintenance as the probable cause.

The Army’s 517,759 M16 rifles received between FY 62 and FY 68 represented just over half of the 1,102,923 weapons delivered to all five services (including the U.S. Coast Guard) between FY 61 (the first 1,000 weapons for ARPA evaluation) and FY 68.

The “urgent requirement” noted in 1965 came from Commander, U.S. Military Assistance Command, Vietnam Gen. William Westmoreland, who requested 170,000 M16s in December of that year. That request was quickly approved and the weapons were introduced rapidly during early 1966.

Unfortunately, after the first few months of tactical employment, in the fall of 1966, U.S. Army units in Vietnam began to report “excessive stoppages and malfunctions” with their new rifles. Preliminary investigations of these reports pointed to a lack of proper training and maintenance as the probable cause.

However, as reliability problems continued to be reported, resulting military, civilian, and political interest prompted three separate “field surveys” of the rifle in Vietnam: October to December 1966; January to February 1967; and April to May 1967.

The bulk of the initial Army survey process focused on maintenance issues and instruction. The Army acknowledges that no after-action report exists for the second survey effort, and subsequent official histories avoid comment on the scope of that visit. The third survey, started in April 1967, was prompted by requests for technical assistance with the XM148 grenade launcher (a prototype 40 mm grenade launcher from Colt Firearms that was soon replaced by the M203 from AAI Corporation), and the team also examined M16s in service with both Army and Marine Corps units.

Apparently not content with the Army’s maintenance-focused activities, the U.S. House Armed Services Committee appointed a special subcommittee to look into the M16 rifle reports. In early June 1967, subcommittee members visited two Marine divisions and elements of five Army divisions in Vietnam.

One subsequent Army memorandum on the congressional visit indicated that “at least 50 percent of the men interviewed had encountered serious malfunctions with the M16, most of them failures to extract.”

“Approximately 50 percent of the men preferred the M14,” it noted. “Most of the men who wanted the M14 felt that it was a more reliable rifle and were concerned about the M16’s possible malfunctions in combat.”

That visit was followed by still more Vietnam field surveys. Conducted by the Office of the Assistant Secretary of Defense (Administration), this round ran from late August to early September 1967. As part of a questionnaire completed by nearly 1,600 men armed with M16s, the team discovered that 83 percent had used the rifle in combat operations, 85 percent reported that it “performed well” in Vietnam, and 87 percent said that they “liked the M16 as an individual weapon.”

Two months later, in November 1967, the Chief of Staff of the Army ordered yet another review of the M16 program, a directive that included yet another field survey of men armed with the M16 in Vietnam. That survey, which ran from late January to early February 1968, looked at how corrective actions previously taken had improved M16 reliability; attempted to identify any current problems being experiences; and evaluated “the general performance and acceptability” of the M16 under combat conditions.

Summarizing the overall findings of the myriad field surveys conducted between October 1966 and February 1968, a June 1968 Army report asserted that the results had been “basically consistent.”

Report conclusions began with the statement that “The M16’s high rate of lethal fire and light weight are qualities particularly suitable for the war in Vietnam.”

“The M16’s high rate of lethal fire and light weight are qualities particularly suitable for the war in Vietnam.”

Acknowledging that failures to extract still occurred “with enough frequency to reduce confidence in the M16,” it also called for both “continued product improvement” and “user effort” as “necessary elements within any program to reduce the M16 reliability problem.”

Other conclusions ranged from the recent introduction of a chromed chamber and the apparent reduction in extraction failures to the need to establish a field malfunction reporting system to “contribute to further improvements in the reliability of the M16.”

In an effort to quantify its conclusions, it added, “Most men armed with the M16 in Vietnam rated this rifle’s performance high; however, many men entertained some misgivings about the M16’s reliability. When asked which weapon they preferred to carry in combat, 85 percent of the men indicated that they wanted either the M16 or its submachine gun version, the XM177.”

Clearly the statements indicate that the Army felt it had “turned the corner” on M16 criticism by June 1968. The truth is that some detractors would continue to vocalize their criticisms for the next five decades. But equally true was the fact that the Army had already started on a path of early product improvements that would eventually grow and give birth to multiple generations of the rifle as well as spin-off variant models.

Part Two of this story, planned for publication in 2014, will look at both these historical developments as well as the current activities under way designed to position the weapon for future decades of service in U.S. military inventories.

This article first appeared in the Defense Fall/Winter 2013-2014 Edition.