.300 AAC Blackout Rifle Upper Assembly - (16" Stainless Barrel & 13.5" M-Lok Handguard)



The AR-15 is the most modular shooting platform in the world, and if you're looking for an easy way to swap calibers, you have to get this upper assembly.  It turns your .223 or 5.56mm-firing AR into one chambered in the .300BLK caliber.  And swapping calibers is fast too.  Just pull out the takedown and pivot pins, remove your current .223 or 5.56mm upper, replace it with this one, and push the pins back in. 


This prebuilt upper assembly comes to you complete with a 16" stainless steel barrel accompanied by a 13.5" free float handguard.  The handguard makes excellent use of the M-Lok attachment system, so you can easily mount your accessories, like foregrips, tac lights, or whatever else.  You can even use your current .223 or 5.56mm mags with the .300BLK caliber.  All that's left is for you to mount either backup sights or an optic of your choice.


Gas System: Pistol-length

Barrel Profile: M4

Barrel Steel: 416R

Barrel Finish: Stainless

Chrome Lining: No

Muzzle Thread: 5/8×24

Chamber: .300BLK

Twist Rate: 1:8

Barrel Extension: M4

Gas Block Size: .750″

Gas Block Type: Low-profile

Muzzle Device: A2 Flash hider

Receiver Material: Forged 7075 T6

Receiver Type: M4

Handguard Type: 13.5″ lightweight M-Lok free float

Bolt Carrier Group Included: Yes

Bolt Steel: 9310 steel, magnetic particle inspected

Bolt Carrier Profile: Full-auto

Charging Handle Included: Yes

Overall Length: 24.5″

Benefits of the 16” Pistol-Length Parkerized AR 15 Upper Assembly:

  • 100% legal to own and ship to your front door
  • Not considered a firearm – no FFL paperwork needed!
  • 4140 steel barrel and Freedom parts kit ensure sub-MOA accuracy
  • Prebuilt upper with gas system removes the guesswork of rifle making
Made in the USA  Lifetime Warranty

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