YHM-71-T : 9.1" 300 BLK OUT BARREL

SKU
181663

This YHM barrel features a 300 AAC Blackout Chamber. Constructed of 4140 chrome moly steel with a threaded muzzle, the barrel is Melonited for ultimate surface protection. The melonite coating provides a thinner surface than chrome-lining, so bore friction is reduced for better accuracy. In addition, melonite is harder than chrome-lining providing a longer wear life.

Our .300 BLK barrels are designed to perform with both subsonic (220 and 208 gr) and supersonic loads. The gas port has been tuned to lock the bolt open on the last round when using subsonic ammunition with a sound suppressor or supersonic ammo without a suppressor. The bolt may not lock back when using subsonic ammunition WITHOUT a sound suppressor installed. Please note that subsonic ammunition can be more prone to malfunction than supersonic ammunition.

The use of this barrel on an AR Pistol is legal, but the use of this barrel on any AR15 rifle/carbine will qualify the firearm as an SBR and the firearm needs to be registered as such.

Due to governmental regulations or manufacturer preferences, some product lines or items may be not be available to export in your country.


Following a manufacturers price increase, we reserve the right to change product prices at any time without further notice.


  • Surface: Smooth
  • Length: 9.1"
  • Weight: 1.1 lbs.
  • Material: 4140 Chrome Moly Steel
  • Chamber: 300 AAC Blackout
  • Twist Rate: 1 in 7"
  • Chrome Lined: No
  • Finish: Melonite QPQ
  • M4 Feed Ramps: Yes
  • Muzzle Thread Pattern: 5/8"-24
  • Gas Port Location: Pistol
  • Exterior Diameter at Gas Port: 0.750"
More Information
Barrel Parts Barrels
Compatibility AR15
Caliber/Gauge 300 AAC Blackout
Ported or Threaded Threaded
Barrel Length (inch) 9.1
Manufacturer Number YHM-71-T
UPC 816701019292
Brand Yankee Hill Machine Co.
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