M21 Rifles | Sniper Weapon System | SWS 4
During the Vietnam War the US Army felt the need of a very accurate sniper system and from that need M21 came into existence. M21 basically is an adaptation of M14 rifle and is a semi-automatic sniper rifle. In 1969 Rock Island Arsenal started converting the M14 to sniper rifles by adding leatherwood 3-9 adjustable ranging telescope. This design was designated as XM21. Later an improved version of this system with a fiberglass stock was designated as M21 in 1975. M21 remained as the primary sniper rifle of the army until it was replaced by M24 sniper weapon systems in 1988. Now it is being mostly used in the US and in Philippines.
M21 was primarily designed in 1969 by Marines Weapons Command, Combat Development Command and Limited Warfare Agency. Currently it is being manufactured by Rock Island Arsenal and Springfield Armory. Its weight is 5.27 kg and it is 1118 mm in length. It has 7.62×51mm NATO cartridge and uses a 20 round box magazine. However 5 and 10 round magazines are also available. Its effective firing range is 822 m. And it has an upgraded variant designated as M25 sniper weapon system.
M21 is a semi-automatic sniper weapon system. It is based upon the design of M14 rifle. During the Vietnam War the U.S. Army demanded a more efficient designated marksman rifle than the existing inventory. As a result of their demand Rock Island Arsenal designed a sniper rifle in 1969 by adding to the basic structure of M14 a leather wood 3-9× adjustable ranging telescope. This version is actually the earlier version of M21 as was designated as XM21. Later this version was improved by adding a fiberglass stock and was designated M21 rifle in 1975. M21 served as the U.S. Army’s primary sniper rifle till 1988. After that it was replaced by more advanced M24 sniper weapon system.
This gas operated rifle fires 7.62×51mm NATO cartridges and chambers detachable box magazines of 5, 10 or 20 rounds of ammo. The Sniper weighs 5.27 kg (11.6 lb.) And is 1118 mm in length with the barrel length of 560 mm. It has an effective firing range of 822 m (900 yards). It has variants like M25 and M21A5. The latter being designed by Smith Enterprise Inc and is commercially known as the Crazy Horse.
Below is a listing of all the M14 Firing Mechanism NSNs (National Stock Numbers). Table 4: Firing Mechanism Items Description Part Number FSN or NSN Comments complete firing mechanism 7790195 original drawing dated July 1958 complete firing mechanism, National Match 9354354 original drawing dated June 1982 sear 7267070 original drawing dated August 1954 sear, National Match […]
Below is a listing of all the M14 Stock and M14 Hand Guard NSNs (National Stock Numbers). Table 5: M14 Stock and Hand Guard Items Description Part Number FSN or NSN Comments butt stock sling swivel 6008889 1005-600-8889 1005-00-600-8889 original drawing dated August 1937 lower butt screw 6008881 5305-600-8881 5305-00-600-8881 slot drive, 0.216 ” diameter x […]
Below is a listing of all the M14 Barrel and M14 Receiver NSNs (National Stock Numbers). Table 1: Barrel and Receiver Group Items Description Part Number FSN or NSN Comments M14 Rifle 7267000 1005-00-283-7695 1005-00-770-3559 original drawing dated March 1955 M14 Rifle with equipment 8413866 1005-00-589-1271 equipment includes sling, four magazines, combination tool and cleaning […]
Back in 2003, the US Army issued a market survey for a 7.62 mm Semi-Automatic Sniper System (SASS). Smith Enterprise responded to the market survey with an M14 rifle variant that was very impressive. The Army should adopt the M14 Rifle for its sniper needs. Below is a copy of SEI’s response to the market […]