M110 SASS is a semi-automatic rifle that is chambered for the 7.62x51mm NATO round

Semi-Automatic Sniper System is intended to replace the M24 Sniper Weapon System used by snipers, spotters, designated marksman, or squad advanced marksmen in the United States Army. However, the Army still plans on acquiring M24s from Remington until February 2010.[1] The U.S. Army ran a competition involving several designs, including ones from Knight's Armament Company, Remington, and DPMS Panther Arms. On September 28, 2005, the Knight's Armament Co. rifle won the competition and was selected to be the M110 Semi-Automatic Sniper System. In April 2007, U.S. Army soldiers from Task Force Fury in Afghanistan were the first in a combat zone to receive the M110. The troops rated the weapon extremely highly, noting the quality of the weapon and its semi-automatic capabilities compared to the bolt-action M24.

It is manufactured by Knight's Armament Company in Titusville, Florida, though the complete system incorporates a Leupold 3.5–10× variable power daytime optic, Harris swivel bipod, AN/PVS-14 night sight and PALs magazine pouches of yet unpublished origin. The company name for the rifle is SR-M110 SASS, but the U.S. Army official designation is the M110 SASS. The rifle has ambidextrous features such as a double-sided magazine release, safety selector switch, and bolt catch.