Wanna squeeze more performance out of your .300 AAC blackout AR when it comes to subsonic rounds? If you plan to get a suppressor, then you need this AR build kit chambered in .300 BLK! Its shorter barrel when paired with a suppressor makes an excellent means of slingin’ lead downrange. This build kit starts with an upper assembly made of an 8.5 inch barrel with a 9 inch lightweight M-Lok handguard. You also get a lower parts kit that comes with a polished trigger for a little smoother performance, a Magpul MOE grip, and the SBA3 adjustable pistol brace by 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.
Includes one lower receiver of your choice OR no lower receiver per your choice.
Barrel
- Chamber: .300 AAC Blackout
- Contour: Heavy
- Length: 8.5"
- Twist Rate: 1:8
- Gas System: Pistol
- Muzzle Threads: 5/8x24
- Feed Ramps: .30-Cal
- Material: 4150 CMV
- Finish: Parkerized
- Process: Button Rifled
- Lining: None
- Extension: M4
- Muzzle: Fluted Flash Can
Handguard
- Attachment System: 9" 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
Unfinished Lower Receiver
- Choose from either a forged Fire/Safe marked, billet Fire/Safe marked, Polymer80 RHINO unfinished lower receiver, or if you already have your own, select No Lower Receiver.
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.
80-Lower.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.
