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AR-15 Upper Assembly – .300 AAC Blackout (10.5″ Parkerized Barrel & 10″ Free Float Quad Rail, 1:8 Twist)

This product has been discontinued.

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SKU: UA300PHB10.518(P)-(10)FFQ


Check out an upper assembly for your AR platform that makes switching calibers quick and painless.  This complete upper assembly is chambered in .300 AAC Blackout, so you can shoot both .223 / 5.56mm and .300BLK.  And the length of this upper assembly’s barrel is closer to being the optimal length in order to make the best of the .300BLK’s ballistic performance.

With this prebuilt upper assembly, you get a 10.5″ parkerized barrel with a 10″ free-floating quad rail.  All that remains is for you to add either backup sights or an optic of your choice.  And yeah, your existing .223 / 5.56mm mags will work with .300BLK rounds.

300 Blackout Upper Barrel Features:

  • 300 AAC Blackout Chamber
  • 10.5″ with Parkerized Finish
  • 4150 Chromoly Steel
  • Contoured Profile
  • 1:8 Twist Rate
  • 5/8 x 24 Thread Pitch
  • A2 Birdcage Flash Suppressor

300 Blackout Upper Receiver Features:

  • 10″ Free Float Quad Rail
  • Pistol-Length Gas System (0.085 Hole)
  • Low Profile Gas Block (0.750)
  • M4 Flat Top Upper
  • .300 Blackout
  • Pistol Gas Tube
  • Charging Handle
  • Standard BCG

No FFL Required

This complete, plug-and-play 300 Blackout Rifle Upper is the most effective way to finish your first 300 Blackout AR 15 without any guess work. The entire barrel and gas system are head spaced and pre-installed, and the whole upper ships to your door with no FFL required and no paperwork needed!

AR-15 Upper Assembly – .300 AAC Blackout (10.5″ Parkerized Barrel & 10″ Free Float Quad Rail, 1:8 Twist)

SKU: UA300PHB10.518(P)-(10)FFQ Category:

This product has been discontinued.


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