By now, the word is out: 300 Blackout works well with shorter barrels, especially in pistol configurations. Subsonic .300BLK rounds also love when you add a suppressor to those shorter barrels. Do it up with this build kit.
To start, you get a prebuilt upper assembly with an 8.5-inch barrel with a 9" lightweight MLOK handguard. You also get a few upgrades. We junked the regular A2 pistol grip and threw in a Magpul MOE grip and trigger guard. We also melted down that old stock trigger and replaced it with a better, polished one. Also, just for giggles and, well you know the other thing, we threw in the SBA3 adjustable pistol brace from SB Tactical.
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: Heavy
- Length: 16”
- Twist Rate: 1:8
- Gas System: Pistol
- Muzzle Threads: 5/8x24
- Feed Ramps: M4
- Material: 4150 CMV
- Finish: Parkerized
- Process: Button Rifled
- Lining: None
- Extension: .30-Cal
- Muzzle: Fluted Flash Can
Handguard
- Attachment System: 9" 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, Carbine
- Pistol Brace: SB Tactical SBA3
- 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 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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