Diamondback Firearms 5.56 AR-15 Mid-Length Barrel Nitride - 16"

SKU: 556M16M50B8
MPN: 556M16M50B8
Manufactured by Diamondback Firearms
4 Reviews


In Stock

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The Diamondback Firearms 5.56 NATO AR-15 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 16” barrel is machined from 4150 Chrome Moly Vanadium Steel and is 6 groove button rifled to ensure consistent accuracy and has a 1:8 twist rate. The mid-length gas system is optimal for reliability and smooth cycling. It is threaded 1/2x28 and features an 11 degree target crown. The final process is a salt bath Nitride finish for an added layer of protection.

  • 16” barrel chambered in 5.56 NATO
  • Machined from 4150 CMV steel
  • Salt Bath Nitride finish
  • Mid-length gas system
  • 1:8 twist rate
  • 6 groove button rifled
  • 11 degree target crown
  • Threaded 1/2x28


Barrel CoatingSalt Bath Nitride
Barrel ContourMedium
Barrel Length16
Barrel Material4150 Chrome Moly Steel
BrandDiamondback Firearms
Caliber Gauge5.56 NATO
Feed RampsM4
Gas Seat Diameter.750
Gas System LengthMid-Length
Thread Pattern1/2 X 28
Twist Rate1:8

Ratings & Reviews

4 reviews

  • 3 stars
  • 0 reviews
  • 2 stars
  • 0 reviews
  • 1 star
  • 0 reviews

Great barrel for the money

by -

Paired this up with a bear creek upper and bcg. Was on zero after just a few shots. Shot 1 moa, 5 shot group, with 55 grain hornady soft points running 26.4 grains of cfe 223. I am very impressed with the accuracy using a mil spec trigger. I have used a couple other Diamondback barrels in the past with the same luck.

Excellent...especially for the price.

by -

True it does not have a dimple for the gas block, but for the price and accuracy, I can't complain. I buldt it for a truck gun and put open flip up sights on it. I sighted it in at 100 yrs with 2 shots then adjust to zero with 4 two shot groups. In all 4 groups the 2 shots were with in .5"-.75" of each other. I know this isn't a true accuracy test, but I am very pleased with the barrel.

No gas block set screw dimples

by -

Beware that the barrel is not dimpled for the gas block set screws. That is the only reason Im giving 4 stars instead of 5. Will have to buy a jig to drill barrel, but its no big deal to me. Other than that Primary Arms is awesome as always with fast delivery and great customer service and for that I am a customer for life

Nice finish, great fit

by -

Got this as part of my budget AR build. It fits great into my Bear Creek upper. The finish is also nice with no marks.