One Horse AR-15 Complete Upper – 7.5″ 300 Blackout

Upgrade your AR-15 build with the One Horse AR-15 Complete Upper in 7.5″ 300 AAC Blackout. This ready-to-run complete upper assembly is purpose-built for shooters who demand reliable performance in a compact, hard-hitting package. The 300 Blackout cartridge is an ideal choice for suppressed shooting, home defense, and hunting applications, delivering impressive terminal performance at close to medium ranges whether running supersonic or subsonic ammunition.

At just 7.5 inches, this barrel configuration makes for a highly maneuverable SBR-style or pistol build that excels in tight spaces without sacrificing the stopping power of the 300 Blackout round. As a complete upper, it arrives ready to mate directly to any mil-spec AR-15 lower receiver, making it an easy and cost-effective way to convert or build your next firearm.

Deep Roots Rifle Co is proud to offer One Horse components at competitive pricing, backed by our knowledgeable staff and commitment to quality. Whether you’re completing a new pistol build, converting an existing rifle, or exploring the versatility of 300 Blackout, this upper is a smart, reliable choice.

Order online today and take advantage of our fast shipping, or stop by our gun store in Eustis, Florida, where our team is ready to help you find exactly what you need for your next build.