The M21 Sniper Weapon System (SWS) is the semi-automatic sniper rifle adaptation of the M14 rifle. The XM21 Sniper Weapon System was used by the U.S. Army in the Vietnam War, and the M21 saw limited action in military conflicts and operations in the late 1960s until the late 1980s. It was used by the U.S. Army Rangers during the Invasion of Grenada in 1983. The XM21 served from 1969 to 1975, and the M21 officially served as the main Army sniper rifle from 1975 to 1988 until the introduction of the M24, which had supplanted the M21 in Ranger Battalions by 1990.
The Morrow Project issues the M21 with a 3X-9X telescopic sight and a Sionics noise suppressor.
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