RADIAN UPPER 18″ 6MM ARC GRAY

Description

The Radian Model 1 upper in 6mm ARC is built for precision rifle work at distance—hunting, long-range target shooting, or any role where the 6mm ARC cartridge’s flat trajectory and efficient ballistics make sense on an AR-15 platform. It suits a shooter who wants a complete, ready-to-run assembly rather than a parts-bin build, and who expects the components to be matched from the start rather than tuned after the fact.

The rifle-length gas system is a deliberate choice on an 18-inch barrel. By drawing gas from farther down the bore, the system allows pressure to drop more before the bolt unlocks, which softens the recoil impulse and slows the bolt’s rearward travel compared to a mid-length or carbine setup. The practical result is a smoother, more controllable shot cycle that makes follow-up shots faster and is easier on brass if you reload. A 1:7 twist rate stabilizes the heavier, high-BC projectiles that 6mm ARC is loaded for—bullets in the 100- to 108-grain range seat well in that twist—so you are not limited to the lighter end of the 6mm projectile catalog.

The 17-inch M-LOK handguard provides a long, uninterrupted attachment surface for bipods, lights, or support-hand accessories without adding bulk. Dead Air’s KeyMo muzzle brake is pre-cut for Dead Air’s KeyMo suppressor mounting system, so the upper is already prepared for that transition without needing a thread adapter or timing shim. The Radian Raptor-SD charging handle is ambidextrous, and the Radian Enhanced Bolt Carrier Group is assembled in-house. Cerakote is applied in Gray throughout. Every Model 1 is assembled and test-fired by a single gunsmith before it ships, and Radian backs the platform with a lifetime guarantee.