.300 AAC Blackout Upper Assembly - (7.5″ Phosphate Barrel & 7″ M-Lok Handguard)



Build the perfect hog gun or personal defense weapon with this shorty .300 BLK AR-15 upper. Boasting a 7.5” barrel, this lil’ upper packs a punch with light and heavy loads. A phosphate coating greatly increases barrel life and performance, while offering better accuracy than chrome-lining. A pistol-length gas system and 1:8 twist rate provide reliable feeding and consistent shot groups with light- or heavy-grain loads. The forged M4 upper receiver provides plenty of rail estate for your favorite optic, irons, or reflex sight. This upper is test-fired and backed by a Lifetime Warranty.

Barrel Features & Specs:

  • Barrel Length: 7.5″
  • Gas System: Pistol Length
  • Barrel Profile: Heavy
  • Barrel Steel: 4150V
  • Barrel Finish: Phosphate
  • Chrome Lining: None
  • Muzzle Thread: 5/8-24
  • Chamber: 300 Blackout
  • Twist Rate: 1:8
  • Barrel Extension: M4
  • Diameter at Gas Block: .750
  • Gas Block Type: Low-Profile
  • Muzzle Device: A2 Flash Hider

Receiver Features & Specs:

  • Receiver Material: Forged 7075 T6 Aluminum
  • Receiver Type: Flattop M4
  • Handguard Type: 7” 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

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