Diamondback Firearms .300 Blackout AR-15 Barrel Nitride - 8.5"

Manufactured by Diamondback Firearms
SKU: 300P8.5H50B8
MPN: 300P8.5H50B8
Manufactured by Diamondback Firearms
7 Reviews
$79.99

In Stock

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Details

Details

The National Firearms Act regulates the configurations of some firearms assembled with barrels under 16” long. Know the NFA laws in your state before purchasing this item.

The Diamondback Firearms 300 Blackout AR-15 Pistol Barrel is machined in house on state-of-the-art CNC machines and are thoroughly inspected at multiple stages of the build process to ensure quality. This 8.5” barrel is machined from 4150 Chrome Moly Vanadium Steel and features 5R rifling to ensure consistent accuracy and has a 1:8 twist rate. The pistol length gas system is optimal for reliability with .300 BLK. It is threaded 5/8x24 and features an 11 degree target crown. The final process is a salt bath Nitride finish for an added layer of protection.

Features:
  • 8.5” barrel chambered in .300 BLK
  • Machined from 4150 CMV steel
  • Salt Bath Nitride finish
  • Pistol length gas system
  • 1:8 twist rate
  • 5R rifling
  • 11 degree target crown
  • Threaded 5/8x24
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Specifications

Barrel CoatingSalt Bath Nitride
Barrel ContourHeavy
Barrel Length8.5
Barrel Material4150 Chrome Moly Steel
BrandDiamondback Firearms
Caliber Gauge300 Blackout
Feed RampsM4
Gas Seat Diameter.750
Gas System LengthPistol
PlatformAR-15
Thread Pattern5/8 X 24
Twist Rate1:8
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

7 reviews

4.6
  • 4 stars
  • 0 reviews
  • 3 stars
  • 0 reviews
  • 1 star
  • 0 reviews

Barrel came damaged

by -

While the finish on the barrel seems ok, the threads on the barrel were damaged. I did not realize this, and also damaged a muzzle brake I was installing onto the barrel. Overall, I am very disappointed in this product

8.5"-300aac barrel

by

Just recently received the Diamondback 8.5" in the mail have not had a chance to build or shoot yet but for the price the barrel looks good it is not dimpled for the gas block and it does have what I would call a blem in the finish but strictly cosmetic but still should not be there on a new barrel and the only markings on it are the number 300 faintly stamped on it but the bore looks good nice and slick and chamber is good also 30° crown and threads are good and it was packed good for shipping so it won't get beat up hopefully it will shoot decent but for the price I was not expecting much ...the 5star rating is for PA They have some of the best prices and always very fast delivery on every purchase I have made with these people

8.5, 300 barrel

by -

I am pleased with the barrel. I have the upper completed and will be completing the rest of the build on Sunday.

8.5"300 aac barrel

by

Follow up to my previous post I have finished my pistol with this 8.5"-300aac barrel and it shoots and functions good and the accuracy is good also I actually bought another one of these barrels after I tested the first one and no problems with either of them

Good value

by -

Shoots good groups, 1" to 1.75" with 147 FMJ ammo. Can't ask for better than that from a 300 blackout.

Great price, & good barrel for pistol or SBR

by

Bought this due to its low price. Finish was good out of the box. Was hesitant about accuracy with this lower cost, but was pleasantly surprised! Hornady factory ammo shot around 1.7" to 2.2" groups at 100. My handloads with 125 Hornady SST bullets ~1.2", and cast lead subsonic loads are around 2.5" to 3" groups. Bullets stabilize well for my suppressor from 110 grain to 220grain.

Will definitely be buying a couple more of these barrels!

Bought two more... Reviewing again.

by -

Bought one of these a number of months ago. Back to review again. Liked it so much, I replaced my 12" 300 blk barrel with this 8.5", topped it with my thermal, and it's great for hunting coyotes with 110 to 125gr supersonic loads, and I also managed to kill a raccoon with 220gr subsonic. Threads seem to be cut nice & concentric, no problems with suppressor.

Bought 2 more, and just recently built one of the two into another nice 300blk Pistol. Will build 3rd one later. Only about 300-400rds through these barrels so far, decent accuracy, and a good bargain. Moderate performance doesn't require lighting your wallet on fire. Quality would be 4-star, bargain is 5-star!