The quick-change barrel has a slotted flash suppressor. The barrel's chamber and bore are chromium-lined and the barrel has four right-hand grooves with a 305 mm (1:12 in) rifling twist rate. Also attached to the barrel is the front sight base, carry handle and gas block (equipped with an exhaust-type gas regulator valve with three settings). The barrel assembly weighs and of the long barrel a portion of is rifled. The MAG takes zero shifts between barrel assemblies into account by making the front sight of the assemblies adjustable with the help of tools.