Description
The 10.5″ Atlas R-One Complete Upper delivers precision performance in a compact, suppressor-ready package. Designed for shooters who demand reliability and adaptability, this upper is available in 5.56 NATO or 300 Blackout, offering versatile capability for close-quarters and mid-range engagements.
Built around a 10.5″ barrel and a pistol-length gas system, this configuration features the Adjustable Gas Block for smooth, consistent cycling — optimized for both suppressed and unsuppressed shooting.
The BCM M-LOK Picatinny rail system offers robust mounting options for lights, lasers, and optics, while the included ergonomic handstop enhances control during high-speed transitions and dynamic shooting.
An ambidextrous charging handle provides flexibility for left- and right-handed operators. The upper is finished with a slip-over compensator, reducing muzzle rise and preparing the platform for suppressor use.
Whether you’re upgrading an existing build or assembling a new AR pistol, the Atlas R-One Complete Upper delivers elite performance, mission-ready right out of the box.
Specifications
| Component | Details |
|---|---|
| Caliber Options | 5.56 NATO or 300 Blackout |
| Barrel Length | 10.5 inches |
| Gas System | Pistol-Length with Adjustable Gas Block |
| Handguard | BCM M-LOK Picatinny Rail – modular and durable |
| Charging Handle | Ambidextrous – universal usability |
| Handstop | Ergonomic – enhanced control under pressure |
| Muzzle Device | Slip-Over Compensator – suppressor-ready, recoil-reducing |
| Upper Type | Complete upper – ready to install on any standard AR-15 lower |



