ONE Armory OH-CU05 10.5″ 300 Blackout Complete Upper Receiver

The ONE Armory OH-CU05 is a purpose-built 10.5″ 300 Blackout complete upper receiver designed for shooters who demand reliability and performance in a compact package. Chambered in 300 BLK, this upper is ideal for suppressed or unsuppressed use, delivering excellent terminal performance at short to medium ranges — making it a top choice for home defense builds, hunting, and tactical applications.

This complete upper receiver arrives ready to install on any standard AR-15 lower receiver, saving you the time and hassle of assembling individual components. Whether you’re building a new AR pistol or SBR, or upgrading an existing platform, the OH-CU05 offers a straightforward path to a capable 300 Blackout configuration.

At Deep Roots Rifle Co, we carry a strong selection of complete uppers and AR components for builders and shooters at every level. Order online for fast shipping nationwide, or visit our gun store in Eustis, Florida, where our knowledgeable staff can help you find the right components for your next build.