Diamondback Firearms DB15 .300 Blackout 16" - AR-15 Rifle

The Diamondback Firearms DB15 .300 Blackout 16" turns your standard AR-15 lower into a hard-hitting .300 Blackout platform that excels suppressed, unsuppressed, and everywhere in between — no new lower, no new mags required.

Chambered in .300 Blackout and running a direct impingement system, the Diamondback Firearms DB15 .300 Blackout 16" is a semi-automatic AR-15 rifle engineered for consistent performance across a wide range of applications.

Quiet Subsonic Performance: Paired with a suppressor, subsonic .300 Blackout ammunition makes this one of the quietest centerfire rifles available — hearing-safe shooting without sacrificing reliability.

Full-Power Supersonic Option: When suppression is off the table, supersonic loads deliver genuine ballistic performance — substantially more energy than 5.56 at short to medium range.

Simple AR-15 Integration: This caliber requires only a barrel and BCG change from a standard 5.56 setup. Lowers, stocks, grips, and magazines remain the same — no new platform required.

Hunting and Defense in One: The .300 Blackout occupies a unique niche: subsonic for quiet defense and pest work, supersonic for hunting and extended-range use from the same rifle.

• Caliber: .300 Blackout
• Barrel Length: 16"
• Gas System: Direct Impingement
• Handguard: Picatinny Quad Rail
• Muzzle Threading: 1/2x28
• Magazine Capacity: 30-Round
• Finish: Type III Hardcoat Anodized
• Origin: Made in the USA

Runs on any mil-spec AR-15 lower with standard STANAG magazines. Only the barrel and bolt carrier group need to be .300 Blackout-specific, making conversion from 5.56 simple.

Built from 7075 aluminum with a Type III Hardcoat Anodized finish, this AR-15 rifle holds up to sustained use without sacrificing dimensional accuracy or function.

Purpose-built for suppressed shooting, home defense, and hunting thin-skinned game at moderate range. A natural fit for suppressor owners who want subsonic capability from an AR-15 lower.

Diamondback Firearms builds a full range of AR-15 rifles with an emphasis on reliability and value, offering solid performance at competitive price points. Made in the USA.