Builder's Grade Complete 9" .22LR LUpper Receiver | A2 | 7" M-LOK | With Bolt Carrier Group and Charging Handle This Complete 9 inch M-LOK upper receiver comes with a 7 inch free float handguard and is built with only the best Mil-Spec components. The heart of this upper is comprised of a 4150 barrel and the bolt is made of all stainless steel construction and we use an anti-jamb dedicated 22 charging handle. Barrel Specifications Caliber 22LR Length 9" Material 4150 Chrome Moly Vanadium Profile Medium Taper Finish SBN Dimpled? No Twist Rate 1:16 Muzzle Thread 1/2x28 TPI Weight 16.23 oz Bolt Carrier Group: Stainless Steel Construction Designed to work with all CMMG and RTB .22LR barrels long lasting and reliable Upper Receiver: Machined from a Mil-Spec 7075 T6 forging Hard Coat Anodized per Mil-A-8625F, Type III M4 Feed ramps Made in the U.S.A. Handguard: 7" free float handguar MIL-STD 1913 Picatinny rail on top 2 M-Lok slots on 3 sides Precision Machined 6000 Series aluminum, for high strength and weight savings Hard Coat Anodized per Mil-A-8625F, Type III, Class 2 Clamp on system for easy assembly Steel Barrel nut to resist movement under heat 8.9 oz with barrel nut and hardware 1.35" Inside Diameter 1.63" Wide Charging Handle: Durable polymer construction with a filled-in, reinforced channel .22 ARC Mil-Spec style Anti-Jam Charging Handle Assembly Please Note:Uppers may present light fouling from our quality control process and/or test firing All semi-auto rimfire firearms operate best with quality copper plated and full powered or high velocity 22lr ammunition.Although .22lr AR builds do not utilize the functionality of a buffer or buffer spring, we still recommend using both to provide a stopping point/wall that prevents the 22 bolt carrier from moving rearward. Using a buffer and buffer spring will prevent light primer strikes. This is true for all Ciener/Atchisson 22 pattern platforms. SKU: BG922LR7A2-BLK UPC: