LWR M6A2 Special Purpose Rifle 5.56mm NATO 16.1 Inch Barrel Black Finish 12 Inch Rail MagPul ACS Adjustable Stock OD Green Finish M6A2 Special Purpose Rifle Features mid-length piston system, enhanced fire control group, a Magpul MIAD pistol grip, and adjustable Magpul ACS stock. Lightweight sculpted 12 inch rail. Cold hammer forged barrel is spiral fluted prior to NiCorr treatment. Adjustable Skirmish low profile front and rear sights. A2 flash hider with 1/2-28 threads. 16.1 inch barrel with one in seven inch right hand rifling.