http://www.history.com/this-day-in-hist ... -defective May 23, 1967: Congressman claims M-16 is defective A public controversy over the M-16, the basic combat rifle in Vietnam, begins after Representative James J. Howard (D-New Jersey) reads a letter to the House of Representatives in which a Marine in Vietnam claims that almost all Americans killed in the battle for Hill 881 died as a result of their new M-16 rifles jamming. The Defense Department acknowledged on August 28 that there had been a "serious increase in frequency of malfunctions in the M-16." The M-16 had become the standard U.S. infantry rifle in Vietnam earlier in 1967, replacing the M-14. Almost two pounds lighter and five inches shorter than the M-14, but with the same effective range of over 500 yards, it fired a smaller, lighter 5.56-mm cartridge. The M-16 could be fired fully automatic (like a machine gun) or one shot at a time. Because the M-16 was rushed into mass production, early models were plagued by stoppages that caused some units to request a reissue of the M-14. Technical investigation revealed a variety of causes for the defect, in both the weapon and ammunition design, and in care and cleaning in the field. With these deficiencies corrected, the M-16 became a popular infantry rifle that was able to hold its own against the Soviet-made AK-47 assault rifle used by the enemy.