Up Next We Have a Brand New Sig Sauer M400 Semi Auto Rifle Chambered in .223 Rem / 5.56 NATO, 16" Barrel, One 30 Round Magazine, Collapsible Stock, Black, RM400-16B-C-SRP, and Comes With All The Magpul MOE Goodies! All in The Factory Box. Sweet Rifle! More From The Internet Below: The Sig Sauer M400 SRP classic is a feature-full AR-15 style tactical rifle that's ready rock out of the box. This reliable carbine features an M1913 railed front gas block instead of a front sight tower, which greatly simplifies optics mounting and reduces weight. This sight-ready platform (SRP) allows the operator to mount an optic without worrying about the sight tower, and the gas block accepts all iron sights designed to attach onto a mlitary spec Picatinny rail. This rifle also features the proven and reliable direct-impingement gas operating system with a rotating locking bolt. A 16" chrome lined and phosphate coated barrel requires very little maintenance, and a 7075-T6 aircraft-grade aluminum forged lower receiver readily accepts high capacity magazines. The M400 SRP Classic is designed for use in law enforcement, military operations, and sport/competitive shooting. Specifications and Features: 5.56 NATO chamber (accepts .223 Remington) Barrel length: 16" 30 Round magazine Standard trigger and safety Overall length: 35.5" Weight: 6.3" 6 Position collapsible stock A2 Flash hider SIG Pistol grip Aluminum receivers Chrome lined barrel 1:7" Twist rate Flat top upper receiver Low profile railed gas block