Global Ordnance 15 Upper 5.56 16" or 12.5" Barrel 1/7 Twist Monolith Barrel Taper Lock MUT Brake

The GO15 16" or 12.5" Upper Receiver is built for performance and reliability. Featuring a 16" or 12.5" Monolith barrel with a 1:7 twist, machined from a single piece of 41V50 ordnance-grade steel, it integrates the gas block and muzzle device for a suppressor-ready, zero-leak setup. Designed as a ready-to-go suppressor host out of the box, it’s built to enhance recoil control, reduce blowback, and maximize reliability. A full-length 1913 Picatinny rail bridges the upper and handguard, providing a rigid, uninterrupted mounting surface for optics, lasers, and accessories. The Monolith barrel is machined from a single piece of 41V50 ordnance-grade steel and features an integrated gas block for zero-leak operation. A thermal-fit oversized extension and interlocking receiver tab improve accuracy and reduce handguard deflection. The bolt head is reinforced with a large diameter and generous corner radius to reduce stress and enhance strength. All-steel feed ramps are fully integrated for reliable feeding. Compatible with Q Plan B and Rearden-style HUB suppressor mounts. These complete uppers are designed for standard AR-15 platforms and compatible lowers.

Features

• Monolith barrel with 1:7 twist – forged from a single piece of 41V50 ordnance-grade steel, integrating the gas block and barrel extension for perfect suppressor alignment and zero-leak operation. Chambered in 5.56 NATO.
• Muzzle device: Monolith Universal Taper brake – Q Plan B and Rearden HUB compatible
• M-LOK handguard with full-length 1913 Picatinny top rail for mounting optics and accessories
• Heavy-duty bolt and all-steel feed ramps (chambered in 5.56). The bolt head is reinforced with a large diameter and generous corner radius to reduce stress and enhance strength.
• Heavy-duty bolt and all-steel feed ramps