Patriot Ordnance Factory Revolution 308 Winchester 16.5in Black Anodized Semi Automatic Modern Sporting Rifle - 10+1 Rounds - The Revolution DI (Direct Impingement) features the same technology, durability, features, and AR-15 size, but in a smaller direct impingement system featuring a 9-position adjustable Dictator gas block and Renegade rail. The DIctator Adjustable Gas Block lets you tune your rifle to the exact operating speed it should be. Its adjustable settings and included a straight gas tube, you and your rifle are set for just about any situation. Its patented E2 dual-extraction technology consists of four small channels cut into the walls of the chamber allowing a small amount of gas pressure to push against the neck of the spent case. The match-grade chrome-moly barrel is 5R button rifled with polygonal rifling for extreme accuracy and finish with a Nitride for unsurpassed strength, heat and corrosion resilience. The Revolution DI rifle also utilizes a non-adjustable single-stage and a mil-spec aluminum anti-tilt buffer tube which features "carrier cradle" extensions to ensure that the carrier is always supported by the buffer tube and has three drain holes.