This Great Lakes Firearms chambered in .450 Bushmaster will get the job done year-round regardless of the season. Starting with precision machined forged aluminum receivers, the flat top upper is matched perfectly to the free-float M-LOK compatible handguard for a seamless Picatinny rail that runs the length of the rifle. It has a black nitride-coated 18" 4150 steel barrel and features a GLFA muzzle brake. - CALIBER .450 BUSHMASTER - MAGAZINE (1) 5rd capacity - BARREL 18", 1:24 Twist, Modified M4 Feed Ramps with GLFA muzzle brake - HANDGUARD 15" Free-float M-LOK compatible - STOCK Adjustable