RADIAN UPPER 18″ 6MM ARC FDE

Description

Radian’s 18-inch complete upper in 6mm ARC is built for the shooter who wants a capable precision platform on an AR-style host — someone running positional matches, hunting medium game at extended ranges, or building a general-purpose precision rifle without starting from scratch. The 6mm ARC cartridge was developed specifically to extract long-range performance from a standard AR bolt face, and the rifle-length gas system on this upper takes advantage of the longer barrel to soften the felt impulse: more dwell time means the bolt unlocks later in the pressure curve, spreading recoil across a longer stroke rather than delivering it as a sharp spike.

The 1:7 twist rate stabilizes the heavier, high-BC 6mm projectiles that make the cartridge worth using at distance — think 103- to 108-grain bullets that would be marginally or inadequately stabilized in a slower twist. That stability is what connects barrel length and cartridge selection into a coherent system rather than a collection of parts. Radian fits a 17-inch M-LOK handguard, which covers nearly the full gas tube and leaves substantial real estate for a bipod, support hardware, or a light without crowding the gas block area.

The Raptor-SD charging handle is Radian’s ambidextrous design, with matched latch geometry on both sides so a support-hand manipulation doesn’t require a compromised grip or a body shift. The Dead Air KeyMo muzzle brake is retained by the same thread interface used by Dead Air suppressors, so the brake is a functional termination point and a ready mounting platform. The enhanced bolt carrier group and hand assembly by a trained gunsmith before the upper ships are part of Radian’s standard production process. The Flat Dark Earth Cerakote finish is applied over the aluminum and steel components throughout.