Quality AR 15 uppers, AR15 parts, AR-15 rifle manufacturer. Friday Harbor, WA
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8.5" 300 Blackout 7" Scorpion Rail Upper
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Your Price $279.99
LOADING...
Perfect for keeping locked and loaded as a close quarters pistol/SBR or hunting coyotes in the woods. Capable of running supersonic ammunition or subsonic ammo..

AR15 300blk Rifle Upper Receiver Assembly:

  • Hardened Arms M4 Feed Ramp Flat Top Receiver
  • Black anodized mil-spec finished upper receiver
  • Feed ramps for increased feeding reliability on barrel and upper
  • T-Marked upper receiver
  • Chrome Moly High End Steel Barrel
  • Black MelonitedFinish
  • Chambered in 300 Blackout
  • 8.5" HBAR Profile barrel with M4 Extension
  • 1/8 Barrel Twist
  • .750" diameter at gas block
  • 5/8x24 threaded muzzle/barrel
  • Low profile gas block
  • Barrel dimpled to secure gas block
  • Pistol length gas system
  • A2 flash hider
  • 7" Scorpion Rail
  • Fits any mil-spec AR15 lower receiver.


Hardened Arms uppers are high end, accurate, head spaced, inspected and test fired prior to shipping. They are built using stringent specs, top quality parts and procedures to ensure maximum reliability and performance. No waiting weeks for parts to come in or uppers to be built to, our website shows real time inventory of what is ready to go out the door to you immediately!

You are responsible for knowing your state laws regarding barrel lengths, pistol, Short barreled rife restrictions. 20% restocking fees if you can not take delivery due to state restriction. Dealer programs are available on our website. Two year warranty against manufacturer defects. Finishes will wear with use, no warranties apply to finish wear.
515 Tucker Ave, Friday Harbor, WA 98250 | sales@hardenedarms.com
Phone: 425-530-0837