The M4-profile 4150 CMV barrel in this upper assembly provides MOA accuracy, thanks to a new .223 Wylde chamber that better handles .223 Remington and 5.56 NATO. Now you can safely shoot both. In addition, we went with a free-float, lightweight M-Lok handguard that provides plenty of rail estate for that bipod, tac-light, front BUIS, and other kit. All other standards come mil-spec in this rifle kit: M16 BCG (works with the side-charging handle with no modifications) and charging handle, housed inside a 7075-T6 forged flattop upper.
What’s Included
This is not a firearm. It includes an assembled upper receiver, bolt carrier group, and charging handle.
AR-15 Upper Assembly Specs
Barreled uppers are assembled in-house before shipment.
Barrel
- Chamber: .223 Wylde (accepts both .223 and 5.56mm NATO)
- Contour: M4/Government
- Length: 16”
- Twist Rate: 1:9
- Gas System: Carbine
- Gas Port: 0.750”
- Gas Hole Dia.: 0.070”
- Muzzle Threads: 1/2x28
- Feed Ramps: M4
- Material: 4150 CMV
- Finish: Parkerized
- Process: Button Rifled
- Lining: None
- Extension: M4
- Muzzle: A2 “Birdcage” Flash Hider
Handguard
- Attachment System: 15" M-Lok
- Finish: Type III Hardcoat Anodized (Mil-Spec)
- Top Rail: M1913 Picatinny
- Material: Billet 6061-T6 Aluminum
- Attachment: Barrel Nut
Upper Receiver
- Profile: M4 Flattop
- Material: Forged 7075-T6 Aluminum
- Finish: Type III Hardcoat Anodized (Mil-Spec)
Bolt Carrier Group
- Profile: M16/Full-Auto
- Steel: Carpenter No. 158 (Mil-Spec)
- Exterior: Black Nitride
- Interior: Black Nitride
- Gas Key: Staked
- Charging Handle: Included
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