Smith & Wesson 12024 M&P15 Sport II OR 5.56x45mm NATO 16" 30+1 Black Black 6 Position Stock Black Polymer Grip Right Hand M-LOK. Smith & Wesson's M&P15 Sport II rifle is the ideal modern sporting rifle. It features a threaded 16" barrel with an Armornite finish. It has also has a 6-position black stock, QD sling swivel attachment point, and a gas block with an integral Picatinny style rail. This model also features M-Lok handguard, 2" M-Lok Picatinny style rail panel, forward assist, and dust cover.