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5.56 AR 15 Upper Assembly - 16" Phosphate Barrel (Classic A2 Handguard), 1:7 Twist Rate

Out of Stock

With so much “tacti-cool” stuff hitting the black rifle market, there’s nothing wrong with taking a step back and building a truly classic shooter. This Classic AR-15 Rifle Build features an old-school A2-style upper, complete with an A2 front sight post, A2-style “birdcage” flash hider, and a traditional forged M4 flattop upper.

Inside, you’re getting a mil-spec lower parts kit and a chrome-lined M16 bolt carrier group with staked gas key and M4 feed ramps. The 4150 CMV barrel promises MOA accuracy with bomb-proof reliability.

What’s Included

This is not a firearm. It includes an assembled upper receiver, bolt carrier group, and a charging handle. 

AR-15 Upper Assembly Specs

Barreled uppers are assembled in-house before shipment.


Chamber: 5.56 NATO Contour: M4/Government Length: 16” Twist Rate: 1:7 Gas System: Mid-length Gas Block: A2-type FSB Gas Port: 0.750” Gas Hole Dia.: 0.070” Muzzle Threads: 1/2x28 Feed Ramps: M4 Material: 4150 CMV Finish: Phosphate Process: Button Rifled Lining: QPQ Nitride Extension: M4 Muzzle: A2 “Birdcage” Flash Hider


Attachment System: A2 Handguard

Finish: Matte black

Top Rail: None

Material: Polymer

Attachment: Delta ring

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:

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

Barrel Length:
Barrel Finish:
Twist Rate:
Handguard Type:
Two-piece / drop-in
Gas System Length:

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.