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M21 (rifle)

U.S. M21
Technical Summary
A.k.a.: 'XM21, M25'
Caliber: 7.62 mm x 51
Firearm action: Gas actuated Semi-automatic
Manufacturer: Rock Island Arsenal
Barrel Length: 22 in (560 mm)
Overall Length: 44 in (1118 mm)
Capacity: 10/20 rd box magazine
Max Range: 875 yd (800 m)
Effective Range: 750 yd (690 m)
Muzzle velocity: 2,800 ft/s (853 m/s)
Rate of Fire: 750 round/min
Trigger Pull: 4.5 lb (2 kg)
Weight Empty: 8.7 lb (3.95 kg)
Weight w/ Mag: 11.0 lb (5.0 kg)

The M21 is the semi-automatic sniper rifle adaptation of the popular M14 rifle. It is chambered for the 7.62 mm NATO round.

Contents

History

The United States Army wanted an accurate sniper rifle during the Vietnam War. It selected the M14 because of its accuracy, reliability, and the ability for a quick second shot. As a result, in 1969, the Rock Island Arsenal converted 1,435 National Match (target grade) M14 rifles by adding a Leatherwood 3-9x Adjustable Ranging Telescope (ART) telescopic sight and furnishing National Match grade ammunition. It was designated the XM21 until 1971 when it became the M21.

The M21 remained the Army’s sniper rifle until 1988 when it was replaced by the M24 SWS (Sniper Weapon System) bolt action rifle.

In 1991, the military updated the M21, primarily by the addition of a McMillan M2A bedded stock and designated it the M25. These are still in use by various Special Operations units. One might note that one of the two Delta Force snipers, Randall Shughart, used one of these rifles during the rescue of Michael Durant during the Battle of Mogadishu in 1993 and is also portrayed using one in the movie Black Hawk Down.


Magazines

In standard military use, the M21/M25 use the same 10 or 20 round box magazines as the other members of the M14 family and weighs 5.27 kg without the scope. The U.S. military never officially authorized or purchased magazines in any other capacity.

See also

External links

10-26-2009 08:16:03
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