SR-25

The SR-25, short for Stoner Rifle-25, is a designated marksman rifle and semi-automatic sniper rifle designed by Eugene Stoner and manufactured by Knight's Armament Company. It uses a rotating bolt and Stoner's gas-operated piston system, loosely based on Stoner's earlier AR-10 chambered in 7.62x51mm NATO, and about 60 percent of its parts are interchangeable with the AR-15 and M16 rifle family. Early rifles were built by Remington Arms with 5R rifling and a free floating barrel attached through the front receiver's handguard. It was designed in the early 1990s and has been in production and in service since 1990.