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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 United States?
Yes. It ships to a licensed FFL dealer in United States; you pick it up there after the background check. Rifles and shotguns ship to a licensed FFL dealer, and your state's rules on age, features and magazine capacity apply at pickup.
Is it in stock?
Yes, at $1074.09. Orders leave within 1-2 business days; shipping is free over $999.

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