When it was first deployed during the Vietnam War, the M16 rifle was hailed as a revolutionary tool for U.S. troops—lightweight, accurate, and seemingly ideal for jungle warfare. In practice, however, the weapon often failed to live up to expectations. Soldiers routinely faced malfunctions such as jams and feeding problems, sometimes occurring in the midst of intense firefights.
These persistent issues undermined confidence in the rifle, leaving many troops unsure whether the M16 could be relied upon in critical situations. In contrast, the AK-47, a straightforward and durable Soviet-designed rifle, gained quiet respect for its ability to function reliably under almost any conditions. Its dependability not only underscored the resilience of opposing forces but also magnified the early frustrations experienced by American soldiers with the M16.
Adoption of the M16 rifle in Vietnam
In 1966, Gen. William Westmoreland, Commander of the US Forces in Vietnam, introduced the M16 rifle as the new standard-issue infantry rifle, replacing its predecessor, the M14. Developed by engineer Eugene Stoner in the late 1950s, it was favored for its accuracy, light weight and the amount of fire it provided.
American troops in Vietnam were given a modified version of the M16, variant XM16E1. The weapon’s adoption was largely in response to the high number of casualties resulting from the enemy’s use of AK-47s. However, controversy surrounding the efficacy of the M16 prevented it from being issued to troops stationed in Europe and the US.
The M16 rifle jammed… A lot
Early versions of the M16 were plagued by significant reliability problems. A frequent issue, called a “failure to extract,” happened when a spent cartridge became lodged in the chamber, resulting in a jam. In some situations, this caused the rifle to function more like a single-shot musket than a fully automatic weapon, leaving soldiers vulnerable during combat.
The most reliable way for soldiers to clear a jammed cartridge was to manually push it out, using a steel rod inserted through the barrel to dislodge the stuck casing.
The M16 was still seen as more effective than the M14
It was later found that the jamming problem was caused by switching to ball powder, which was meant to boost the muzzle velocity to 3,250 feet per second.
Even with these problems, the M16 was still seen as better than the M14. In fact, the US Army even called it the best rifle for combat in Vietnam. To fix the issues, they improved training, adjusted the gunpowder formula, and made sure cleaning kits were widely available—but not before a Congressional report brought attention to the problems.
A harrowing report is released
By 1967, nearly 80 percent of the 1,585 soldiers surveyed reported experiencing stoppages with the M16 rifle during combat. Many of these troops expressed their frustrations in letters to family members, detailing concerns about the weapon’s reliability. These letters were subsequently forwarded to members of Congress, prompting the House Armed Services Committee to take notice of the growing problem.
The congressional response proved effective, resulting in the creation of a Subcommittee to investigate the M16 rifle. After a thorough review, the committee’s report validated the soldiers’ complaints, concluding that the Army had failed to provide adequate training on the new weapon, neglected to ensure ammunition compatibility, and did not supply sufficient cleaning kits to prevent malfunctions.
Despite these findings, the military continued issuing the M16 to troops. As reliability issues persisted, confidence in the rifle eroded among service members, many of whom began seeking alternative solutions in the field.
Picking up the AK-47
During the Vietnam War, many American troops came to respect the AK-47, the standard rifle used by the Viet Cong and North Vietnamese forces. In the 1950s, China produced its own version, known as the Type 56 or AK-56. This model was slightly shorter and lighter than the original Soviet rifle and could be fired in either semi-automatic or fully automatic modes.
The AK-47 earned its reputation for being extremely durable and easy to handle. It continued to function in harsh environments and needed very little upkeep. Because of its straightforward, rugged construction, even inexperienced fighters could use it effectively—a major advantage in the intense heat and humidity of Southeast Asia’s jungles.
American soldiers often grew frustrated with the M16, especially because it had a well-known habit of jamming during combat. In contrast, the AK-47 earned a reputation for reliability, and many troops began to favor it. Soldiers obtained the rifles in various ways—some captured them from enemy forces, while others acquired them through informal trades or secret purchases. Despite widespread reports of malfunctions in the field, military officials maintained that the M16’s issues were caused by improper use or lack of maintenance, rather than flaws in the weapon’s original design.