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Diamondback Firearms DB15 Combo 5.56 NATO .300 Blackout Black Hard Coat Anodized Rifle

The Diamondback Firearms DB15 Combo is a semi-automatic AR-pattern rifle package designed around interchangeable 5.56 NATO and .300 Blackout configurations. Both barrels measure 16 inches, while the black hard-coat anodized receiver set and adjustable Magpul MOE stock provide a durable, familiar platform for range use, training, and recreational shooting. A flat-top receiver with an optic mounting rail supports the addition of a compatible red dot sight or riflescope.

Key features

  • Interchangeable 5.56 NATO and .300 Blackout configurations provide versatile ammunition options
  • Two 16-inch barrels support balanced handling and practical range performance
  • Semi-automatic operation with 30+1 capacity supports efficient target practice
  • Black hard-coat anodized receiver finish helps resist wear from regular use
  • Adjustable Magpul MOE stock allows the length of pull to be tailored to the shooter
  • Flat-top optic mounting rail makes the rifle ready for a compatible sighting optic

The DB15 Combo delivers a flexible AR-pattern rifle platform with two popular chamberings in one package.

Diamondback Firearms DB15 Combo 5.56 NATO .300 Blackout: quick facts

What caliber is the Diamondback Firearms DB15 Combo 5.56 NATO .300 Blackout?
It is chambered in 5.56 NATO, .300 Blackout.
How many rounds does it hold?
30+1 rounds.
How big and heavy is it?
Barrel length 16 inches.
What kind of action does it use?
Semi-Automatic.
Is it optic ready or threaded?
Optic ready: Yes; threaded barrel: Yes.
What sights and finish does it have?
Sights: Standard Sights; finish: Black Hard Coat Anodized.
Is it new or used?
New, in the original packaging.
Can I buy it in Utah?
Yes. It ships to a licensed FFL dealer in Utah; you pick it up there after the background check. Rifles and shotguns ship to your chosen Utah FFL dealer for the background check and pickup, with no state waiting period.
Is it in stock?
Yes, at $1074.09. Orders leave within 1-2 business days; shipping is free over $999.

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