The Ruger AR-556 is a direct-impingement carbine built on a forged 7075-T6 aluminum receiver with a 16-inch cold hammer-forged barrel. It ships with Ruger Rapid Deploy folding sights and is priced as a no-frills entry into the AR-15 market. Type: Semi-Auto Rifle Action: Gas-Operated Caliber: 5.56x45mm Capacity: 30 Year introduced: 2015, USA Weight: 6.5 oz Overall length: 32.3" Status: Active Intended use: Home Defense, Patrol, Range