Compact and capable .300 BLK was designed to be right at home in AR15-pattern firearms like the CMMG Mk4 platform. Originally created for optimum performance in subsonic suppressed and short-barrel applications .300 BLK in supersonic ammo loadings has evolved into a popular competitor to other intermediate cartridges like 7.62x39. No matter what the application is this BANSHEE(TM) is built to fit the bill.