The M&P15-22 is Smith & Wesson's dedicated .22 LR rimfire AR-pattern rifle. Not an AR-15 converted to .22 LR but purpose-built from the ground up in the AR silhouette with a 16.5-inch barrel. Type: Rifle Action: Semi-Automatic Caliber: .22 LR Capacity: 25 Year introduced: 2009, USA Weight: 5.7 oz Overall length: 35" Status: Active Intended use: Training,Plinking,Competition