Rise Armament Upper Receiver Complete Upper Features The Rise Armament Upper Receiver centers on an 18 inch 416R stainless steel barrel a material chosen by precision rifle builders for its combination of accuracy potential and corrosion resistance. Chambered in 6mm ARC the barrel is cut with a 1:7 twist rate to stabilize the longer heavier bullets that make the cartridge effective at extended ranges. The barrel is threaded 1/2x28 at the muzzle giving shooters the option to add a muzzle brake or suppressor for recoil management or reduced sound signature. A black Cerakote finish on the barrel protects it from the elements while contrasting against the grey aluminum receiver for a distinctive look. Built on an aluminum receiver the upper keeps weight manageable while maintaining the strength needed for repeated firing of a long-range cartridge like 6mm ARC. As a complete upper it is ready to install onto a compatible AR-15 lower giving builders a straightforward path to a 6mm ARC precision rifle without machining or fitting a barrel themselves. The combination of an accurate barrel a stabilizing twist rate and a threaded muzzle makes this upper well suited to long-range target shooting and hunting applications. For AR-15 owners looking to add a dedicated 6mm ARC precision upper to their collection the Rise Armament Upper Receiver delivers accuracy-focused components in a ready-to-install package. Rise Armament Upper Receiver Complete Upper Specifications Manufacturer: Rise Armament Model: Upper Receiver Caliber: 6mm ARC Color: Grey Barrel Finish: Black Cerakote Barrel Material: Stainless Steel Twist Rate: 1:7 Receiver Material: Aluminum Thread Pattern: 1/2x28 Barrel Length: 18 Available At: GrabAGun