300 Blackout AR 15 Rifle Kit – 16″ Parkerized Heavy Barrel, 1:8 Twist Rate with 15″ M-Lok Handguard

Please note: We strive to provide the most accurate photographs of our product wherever possible. Due to availability limitations and supply chain constraints, slight variations of the handguard of this upper assembly may occur in the aesthetics of the skeletonizations in between the M-Lok sections.
For the long-range guys and gals who require a do-it-all AR with a .30-cal, this 300 Blackout build kit provides a lightweight rifle that can shoot suppressed or un-suppressed with supers and subs all day (and night, for the hogs). With a 16″ barrel forged from 4150 chrome moly vanadium with a 1:8 twist providing optimal velocity and stability for all grains and loads, this rifle kit will allow you to achieve as much performance as your .300BLK ammo can give you.
What’s Included
This kit is not a firearm. It includes an assembled upper receiver, bolt carrier group, lower parts kit, and buffer assembly with buttstock. 
300 BLK Rifle Kit Specs
Barreled uppers are assembled in-house before shipment.
Barrel

Chamber: .300 AAC Blackout
Contour: Heavy
Length: 16”
Twist Rate: 1:8
Gas System: Pistol
Gas Port: 0.750”
Gas Hole Dia.: 0.070”
Muzzle Threads: 5/8×24
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: 9310 Tool, HPT/MPI-tested
Exterior: Black Nitride
Interior: Black Nitride
Gas Key: Staked
Charging Handle: Included

Lower Receiver Parts

Buffer System: Mil-spec, Carbine
Buttstock: Mil-spec, M4-type
Parts Kit: Mil-spec, single-stage

Lower receiver not 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.