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AR-15 Upper Assembly – .300 AAC Blackout (16″ Parkerized Barrel & 13.5″ M-Lok Handguard, 1:8 Twist)

$399.99 $364.99 (You Save $35.00)

Out of stock

Out of stock

Free Shipping on all orders $325+!

SKU: 3001618(B)-MLOK(135)


Looking for an easy way to make your AR-15 shoot the popular .300 AAC Blackout round instead of its standard 5.56mm round?  Get this upper assembly!  Chambered in .300BLK, this bad boy makes it easy to swap back and forth from 5.56mm to .300BLK in only a few seconds.  Pull the takedown and pivot pins and simply swap your old upper assembly with this one.  That’s really it!

This complete upper assembly comes to you prebuilt with a 16″ parkerized barrel coupled with a 13.5″ M-Lok handguard.  All you have to do is add either the backup sights or optic of your choice.  Hell, your current 5.56mm mags will even work with the .300BLK rounds.


Gas System: Pistol-length
Barrel Profile: M4
Barrel Steel: 416R
Barrel Finish: Parkerization
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

No FFL required Made in the USA Lifetime Warranty

Shipping Restrictions only ships within the United States. Federal legislation dictates we cannot ship our products internationally. 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 (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.
We try our best to keep our shipping page current, but laws change daily. 

AR-15 Upper Assembly – .300 AAC Blackout (16″ Parkerized Barrel & 13.5″ M-Lok Handguard, 1:8 Twist)

$399.99 $364.99 (You Save $35.00)

Out of stock

Out of stock

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Free Shipping on all orders $250+!


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