.300 AAC Blackout Upper Assembly - (7.5" Nitride Barrel & 9" Lightweight M-Lok Handguard)



This 7.5” .300 BLK AR-15 upper’s perfect for building the ultimate personal defense weapon, range toy, or compact medium-to-close-range shooter. Featuring a mil-spec heavy barrel made from 4150 CMV, this upper promises superior accuracy and barrel life. The included nitride finish offers longer barrel life than a chrome-lined finish with better precision. Finishing off this upper is a mil-spec, forged 7075 T6 flattop upper and a lightweight, free-float M-Lok handguard. This upper ships test-fired and is backed by a Lifetime Warranty. Pair with a buffer system, 80% lower, and lower parts kit, and you'll have all the parts you need to complete this upper as a new pistol or SBR!

Barrel Features & Specs:

  • Barrel Length: 7.5″
  • Gas System: Pistol Length
  • Barrel Profile: Heavy
  • Barrel Steel: 4150 CMV
  • Barrel Finish: Nitride
  • Chrome Lining: None
  • Muzzle Thread: 5/8-24
  • Chamber: 300 Blackout
  • Twist Rate: 1:7
  • Barrel Extension: M4
  • Diameter at Gas Block: .750
  • Gas Block Type: Low-Profile
  • Muzzle Device: Fluted Flash Can

Receiver Features & Specs:

  • Receiver Material: Forged 7075 T6 Aluminum
  • Receiver Type: Flattop M4
  • Handguard Type: 9” Lightweight M-Lok Handguard
  • Bolt Carrier Group Included: Yes
  • Bolt Steel: Carpenter 158 Steel
  • Bolt Carrier Profile: Full-Auto (M16)
  • Charging Handle Included: Yes 
No FFL required  Made in the USA  Lifetime Warranty

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

80-Lower.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.