Bushmaster M17S

The Bushmaster M17S was a semi-automatic bull-pup rifle sold to civilians in the United States and the first rifle of that layout offered on the American commercial market. It descends from Australian designs of the mid-1980s: Armtech developed the 5.56x45mm NATO C60R as a possible Australian Army rifle, the army chose the Steyr AUG instead, and the design passed to Edenpine, which developed it into the ART-30 and SAK-30. Edenpine marketed it in the United States through Bushmaster Firearms International of Maine from 1992 until Edenpine folded in 1994, after which Bushmaster held the rights and built the rifle until 2005. It uses a short-stroke gas piston, a 21.5 inch barrel and 10 or 30 round magazines, and its barrel sleeve was lengthened to prevent fitting a flash suppressor.