SMITH & WESSON M&P 15 AXE 300BLK SEMI AUTO PISTOL Built on the proven M&P15 platform, the AXE SBR is designed for reliable performance across a wide range of applications. The integration of Gemtech's GVACA(R) system helps reduce gas blowback when running suppressed, improving overall shooting comfort. Lightweight, durable, and purpose-built, it delivers a balanced combination of control, adaptability, and consistent function in demanding conditions. SPECS Caliber: .300 Blackout. 8" 1:7.5" twist 5R rifled barrel w/ArmorniteA(R) finish. GVACA(R) direct impingement gas system. 5/8x24 threaded barrel w/thread protector. Mfg: Smith & Wesson