Security Police Weapons The M16: American Icon Since the 1960s, the 5.56mm M16 and its later variants have been the standard rifle for all U.S. armed services. It has also been widely exported to military services around the world. The U.S. Air Force was the first military service to acquire and adopt the M16. Personally championed by Gen. Curtis LeMay, the first contract was issued to Colt Firearms in May 1962 for the purchase of Armalite AR-15 Model 01 rifles. Developed from the larger Armalite AR-10 design in the 7.62x51mm caliber, the much smaller AR-15 in 5.56x45mm caliber replaced the two World War II vintage .30-cal. M1 and M2 carbines then in use by the U.S. Air Force Security Police. It also quickly found favor among Air Force personnel assigned to the growing conflict in South Vietnam. The U.S. Air Force M16 design was later modified and adopted for use by the U.S. Army as the XM16E1 in 1965. The M16, including all variants, is the most mass produced U.S. military weapon in history with over 8 million weapons manufactured to this date. The M16 possessed several novel features for its time. The raised gunsight permitted a straight stock. This gunsight could also be used as a handle to carry it. At under 8 lbs loaded, the M16 was more than two pounds lighter than a loaded M14. This lower weight was due in part to the use of a fiberglass stock and grip instead of the more traditional wood. Colt Model 01 AR-15 Rifle As the first of the M16 rifle family, these ultra-modern semi- and full-automatic rifles were chambered for the .223-cal. cartridge which was later designated as 5.56mm. The first production contract weapons were delivered to the U.S. Air Force in the early 1960s with many being directed to units in Southeast Asia. The weapon on display is one of the first thousand (serial number 000836) of the M16 family ever produced and it remains in its original issue configuration with a 20-round magazine. Click here to return to Protecting the Force: Air Base Defense.