Knight's Armament SR-15 Individual Weapon System with 14.5-inch barrel, the military-specification version of the SR-15 produced for USSOCOM. Type: Rifle Action: Semi-Auto Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 2008, USA Weight: 98 oz Overall length: 31" Status: Active Military use: Yes Intended use: Military special operations, law enforcement CQB