The newest addition to the Ruger AR-556 MPR family features a PROOF Research (Global Leader in Composite Technology) carbon fiber barrel. The attractive, 18, barrel is chambered in .223 Wylde, a hybrid chamber that safely, accurately, and reliably functions with both .223 Remington and 5.56 NATO ammunition. The muzzle is finished with Ruger's radial port muzzle brake. The rifle also features the Ruger Elite 452 two-stage trigger, Magpul PRS Lite stock, and an MOE-K2 grip.