Follow us on
Add us on

If You Can "ADD TO CART" - Then We Have It IN STOCK and Shipping ASAP

Call or Text (For Fastest Response) 715-271-8361

View This Upper On Our Website - CLICK HERE TO VIEW 8.5"  300 Blackout UPPER

Old Testament Firearms offers this phenomenal 8.5-Inch AR15 Rifle Upper Receiver Group chambered in 300 Blackout with pistol gas system for reliable operation. It provides exceptional reliability and durability!

Regardless of how much you shoot, you should never have to worry about your firearm functioning properly and with our OTF Upper Receiver Group - You won't have to. Our Gen2 Free Float M-LOK Handguard is 7" in length and locks up solid with anti-rotation tabs and offers M-LOK slots for mounting of your weapon lights, foregrip or grip panels.

It is built with quality, made in the U.S.A. components to provide reliable function even after thousands of rounds! We don't strive to sell the lowest price upper receiver groups, but we do aim to provide the best value for the money without sacrificing any quality or reliability.


This 300 Blackout Upper Receiver Group consists of the following components:

  • 8.5" Nitride Finished 300 Blackout Barrel - Medium Profile - Pistol Length Gas System - 1/8 Twist
  • 7" Free Float OT Firearms M-LOK Gen 2 Handguard
  • OT Firearms Forged 7076-T6 M4 Upper Receiver
  • Nitride Finish Low-Profile Gas Block
  • Nitride Finish Pistol Length Gas Tube


Concerned about quality? Don't Be! Old Testament Firearms stands behind their products! All Complete AR15 / LR308 Assemblies and Firearms come with a LIFETIME WARRANTY against manufacturing defects and workmanship! Our components are meant to be put to work!