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Davidson Defense - .300 Blackout AR-15 Pistol Upper Assembly - 8.5" Nitride Barrel, 1:7 Twist with 9" Honeycomb M-LOK Handguard

Out of Stock

Check out this wicked little 300 BLK pistol upper: It features a 9" M-LOK "honeycomb" rail measuring just a hair longer than the 8.5" barrel, providing that sleek locked-up look when you thread on a can. Or, just roll with the provided "can"-style flash hider. It looks great and helps tame those fireballs.

Our 300 BLK pistol uppers and test-fired and cycled to ensure reliability when running supersonic and subsonic ammo. Pair it up with your favorite lower, or use it to complete a custom build! Check out our lower assembly components to make things easy.

PLEASE NOTE: This is not a firearm. This is a prebuilt upper assembly only. It includes an assembled upper receiver, bolt carrier group, and charging handle. 

New to ARs? Here's how to build an AR-15.

AR-15 Rifle Upper Assembly Specs

Barreled upper assemblies are assembled in-house before shipment.


  • Chamber: .300 AAC Blackout
  • Contour: Straight
  • Length: 8.5”
  • Twist Rate: 1:7
  • Gas System: Pistol
  • Gas Port: 0.750”
  • Gas Hole Dia.: 0.070”
  • Muzzle Threads: 5/8x24
  • Feed Ramps: M4
  • Material: 4150 CMV
  • Finish: Nitride
  • Process: Button Rifled
  • Lining: None
  • Extension: M4
  • Muzzle: "Can"-style flash hider


  • Attachment System:  9" M-Lok, Skeletonized
  • Finish: Type III Hardcoat Anodized (Mil-Spec)
  • Top Rail: M1913 Picatinny
  • Material: Billet 6061-T6 Aluminum
  • Attachment: Barrel Nut 

Stripped 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

WARNING: Handling firearms parts and accessories can expose you to lead and other petroleum products known to the State of California to cause cancer and reproductive harm. For more information go to: www.P65Warnings.ca.gov

Shipping Restrictions

Shipping of various parts and/or accessories are prohibited to states and locales (ie New Jersey, California, New York, etc…) with restrictions against certain parts and/or accessories or "assault weapons" (i.e. states with high-capacity magazine restrictions, manufacturing of semi-automatic weapons, etc..). It is your responsibility to be aware of your local firearms laws before purchasing from our website or machining a firearm. We try our best to keep our shipping page current, but laws change daily.

GunBuilders.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.

.300 AAC Blackout
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We are a national retailer of individual components and not all products depicted on this website are legal in every state. Shipping of various products found on this website are prohibited to some states (such as California, Connecticut, District of Columbia, Hawaii, New Jersey, New York, Rhode Island, and Washington). The information, pictures, text or products presented on this website are not a representation by us, and should not be understood by you, that any product or completed firearm is legal to assemble or own in your state of residence. We encourage each and every builder to perform their own research about the state and federal laws that apply to them. It is your responsibility to understand the law and we encourage you to consult with an attorney or your local ATF representative.