.300 Blackout AR-15 Pistol Kit – 8.5″ Nitride Barrel, 1:7 Twist with 7″ M-LOK Handguard

Lightweight, subsonic-friendly, and suppressor-ready.
This 8.5″ 300 Blackout AR pistol kit provides the perfect configuration for slappin’ a can on the muzzle and running some heavy subsonics for suppressed fire. Thanks to a fast 1:7 twist rate and free-floating, skeletonized handguard, this 300 BLK kit is lightweight, accurate, and able to host any suppressor on its 5/8×24 TPI muzzle.
This includes all components required to assemble a ready-to-fire pistol, except for a stripped lower receiver. This kit’s compatible with all “retail” stripped lowers or fabricated 5.56/.223-chambered AR-15 80% lowers.
Note: Due to ATF rule 2021R-08F, any pistol with a stabilizing brace is considered a short-barreled rifle (SBR), and is therefore considered a National Firearms Act item requiring a federal tax stamp.
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 pistol brace. 
New builder? Here’s how to build an AR-15.
AR-15 (300 BLK) Pistol Kit Specs
Barreled uppers are assembled in-house before shipment.
Barrel

Chamber: .300 AAC Blackout
Contour: Straight
Length: 8.5”
Twist Rate: 1:7
Gas System: Pistol
Muzzle Threads: 5/8×24
Feed Ramps: M4
Material: 4150 CMV
Finish: Nitride
Process: Button Rifled
Lining: None
Extension: .30-Cal
Muzzle: Pinhole Compensator

Handguard

Attachment System: 7″ Lightweight 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

Lower Receiver Parts

Buffer System: Mil-spec Tube, Carbine (3.0 Oz) Buffer
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.

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