CMMG AR-15 Sierra A3 Flat-Top Upper Assembly 22 Long Rifle 1 in 16" Twist 16" Barrel Chrome Moly Matte with M4 Handguard, Flash Hider

Product #: 210789 CMMG #: 22B7CC2 UPC #: 852005002981
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The CMMG AR-15 Sierra .22 Caliber A3 Upper is a complete dedicated rimfire AR-15 conversion upper that maintains compatibility with all the same parts and accessories that fit your full caliber AR's. The 22 Long Rifle conversion bolt, along with the barrel's true 22 LR chamber and proper 1/16" twist rate, make for a truly accurate rimfire AR-15 for inexpensive practice, small game hunting, and introducing young or new shooters to the AR-15 platform.

CMMG's Sierra rimfire uppers feature many significant improvements over previous designs, enhancing functionality, reliability, and ease of use. Prominent among these improvements are an Anti-Jam Charging Handle, Live Round Extraction ability, and Gas Deflector. CMMG's durable Weapons Armament Surface Protection (WASP) Melonite treatment has been applied to the barrel and surface-hardens the steel, extending barrel service life by reducing friction in the bore and lessening bore surface wear.

The Sierra upper is ready to drop on to any standard mil-spec lower receiver, all that's needed are a compatible magazine and a pile of 22 LR ammunition to start enjoying some inexpensive and fun time at the range! Compatible with Black Dog Machine and CMMG rimfire AR-15 magazines (not included). CMMG recommends the use of Plated 40 grain High Velocity 22 LR ammunition for optimal functioning.

Technical Information:
  • Upper Receiver: A3 Flat-Top w/Ceramic Finish
  • Barrel Length: 16"
  • Barrel Contour: M4
  • Barrel Material: Chrome Moly Steel
  • Muzzle Thread Pattern: 1/2"-28
  • Chrome Lined: No
  • Barrel Finish: WASP Melonite
  • Twist Rate: 1 in 16"
  • Chamber: 22 Long Rifle
  • Muzzle Device: A1 Flash Hider
  • Gas System Length: None, Blowback
  • Gas Block Diameter: 0.750"
  • Handguard: Polymer M4-Style
  • Sights: None, Single Rail Gas Block/Front Sight Base
  • Extras: Gas Deflector, Anti-Jam Charging Handle, Non-Functional Forward Assist Plug, Live Round Extraction
  • Magazine Not Included, Compatible w/Black Dog Machine & CMMG Magazines

Please Note: Installation of AR-15 upper assemblies with certain features including, but not limited to: flash hiders, bayonet lugs, and threaded muzzles may violate state and/or local laws.

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