.300 Blackout Ammo Overview

The .300 AAC Blackout (7.62x35mm) represents a revolutionary approach to AR-platform versatility. Developed by Advanced Armament Corporation in 2011, this cartridge was engineered to provide both supersonic and subsonic capability while maintaining full compatibility with standard AR-15 magazines and bolts. It delivers .30 caliber power from an AR-15 platform with only a barrel change.

The cartridge's dual-purpose nature makes it uniquely versatile. In its supersonic form, it roughly matches the ballistics of the 7.62x39mm, making it effective for hunting and tactical applications out to 300 yards. In its subsonic configuration, it offers exceptional suppressed performance while maintaining accuracy and terminal effectiveness. This flexibility has made it increasingly popular among hunters, competitive shooters, and defensive users who appreciate its adaptability and AR-15 compatibility.

What .300 Blackout Does Best

The .300 Blackout's versatility allows it to excel in multiple roles, though its primary strengths lie in its ability to serve as both a supersonic hunting/defensive round and a superior subsonic suppressed option. This dual-purpose nature, combined with AR-15 compatibility, makes it uniquely capable in several key applications.

Suppressed Shooting

• Exceptional performance with subsonic loads and a suppressor, offering superior sound reduction while maintaining accuracy and terminal effectiveness

Hunting

• Effective on medium game out to 300 yards with supersonic loads, while subsonic loads work well for closer range hunting where noise reduction is valuable

Home Defense

• Supersonic loads offer improved terminal performance over 5.56 NATO, while subsonic loads minimize overpenetration risks and protect hearing when suppressed

Popular Manufacturers

Supersonic Manufacturers

• Hornady: Critical Defense and Black ammunition lines
• Federal Premium: Fusion MSR and Gold Medal Match
• Barnes: VOR-TX with solid copper projectiles
• Nosler: Ballistic Tip and Match Grade offerings
• Winchester: PDX1 Defender and USA lines

Subsonic Specialists

• Discreet Ballistics: Purpose-built subsonic loads
• Gorilla Ammunition: Specialized subsonic offerings
• Sellier & Bellot: Affordable subsonic options
• Underwood: High-performance subsonic loads
• Freedom Munitions: Custom subsonic offerings

.300 Blackout History

The .300 AAC Blackout emerged from a U.S. military request for a 30-caliber cartridge capable of both supersonic and subsonic operation in the M4 platform. Advanced Armament Corporation (AAC) developed the cartridge in 2011, basing it on the obsolete .300 Whisper wildcat cartridge but ensuring SAAMI standardization.

The design objectives were specific: create a cartridge that could deliver .30 caliber power from an AR-15 platform while maintaining compatibility with existing magazines and parts. The cartridge needed to function reliably in both supersonic and subsonic configurations, with particular emphasis on suppressed performance.

While its military adoption has been limited, the .300 Blackout has found significant success in the civilian market. Its ability to offer both hunting-capable supersonic performance and exceptional suppressed characteristics has made it popular among shooters seeking a versatile AR-15 cartridge. The growing interest in suppressed shooting and home defense has further cemented its position in the market.

Today, the .300 Blackout continues to evolve, with manufacturers developing increasingly specialized loads for both supersonic and subsonic applications. Its success has influenced the development of other cartridges and helped establish the viability of dual-purpose rifle rounds in the civilian market.