Faxon Gunner 9" 1:5 338 ARC Barrel

The Faxon Gunner 9" .338 ARC barrel is the short, suppressor-host length for Hornady's .338 ARC cartridge, built around the heavy 307gr Sub-X subsonic load. It runs on 6.5 Grendel Type 2 (.136) bolts and feeds from DuraMag 400 Legend magazines, the same component recipe as longer .338 ARC barrels, in a package short enough to balance a can without turning the rifle into a pike.

The 1:5 twist is the defining choice here. It is not Hornady's official .338 ARC spec; Hornady runs 1:8 to cover the full load range. The 1:5 is a barrel-maker fast-twist option that Faxon offers on short subsonic lengths, where over-stabilizing the long 307gr Sub-X projectile out of a 9-inch barrel drives more violent terminal expansion than a slower twist delivers. It is a deliberate subsonic terminal-performance barrel, not a general-purpose one.

Because the barrel is under 16 inches, the host firearm has to be configured legally as either a Form 1 SBR or a pistol/brace build. Under the One Big Beautiful Bill Act, the federal making tax on an SBR is now $0, and ATF eForm 1 approvals are running on the order of days to a couple of weeks. The barrel itself is 416R stainless with a nitride finish, 5R rifling, the Gunner pencil/government hybrid profile, a pistol-length gas system, and 5/8x24 muzzle threads for .338 ARC muzzle devices and a .338-rated suppressor. The .338-inch bullet exceeds a .30-cal bore, so a .30-caliber can is not rated for it; thread on a .338 Lapua-rated can like the SilencerCo Omega 36M.