Ruger's AR-556 MPR rifle has a pistol-length gas system which provides smoother operation and reduces felt recoil. The matte black oxide chrome-plated bolt carrier inside diameter and chrome-plated gas key inside diameter provides exceptional resistance to hot gases. Its lower receiver is fitted with Magpul MOE grip and a Ruger Elite 452 two-stage AR-trigger which offers a smooth, crisp, 4.5 pound trigger pull. The flattop upper receiver is made from forged aerospace-grade 7075-T6 aluminum, and includes a forward assist, dust cover and brass deflector.