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: 8.5”
- 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.
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