The SR-556 offers Ruger's legendary rugged reliability and comes factory standard with a host of accessories that today's shooters demand. The SR-556 employs a patent-pending, chrome-plated, two-stage piston driven operating system that provides the user with a cleaner, cooler running, reliable firearm that is truly state-of-the-art. The chrome-lined gas block and chrome-plated piston and regulator work together to provide a smooth power delivery stroke to the bolt carrier. The by-products of the gas system are vented out the bottom of the gas block, away from the bolt carrier, keeping the action clean and free from contaminants.
Every SR-556 is built with a hammer-forged, chrome-lined mil-spec 41V45 barrel that ensures accuracy and longevity. A Hogue Monogrip pistol grip adds comfort when carrying or shooting. Other features a chrome-plated bolt, a one-piece bolt carrier and extractor, and a set of rail covers.