The 6mm ARC cartridge was introduced by Hornady in 2020. Almost immediately, Black Hills Ammunition recognized this round as a homerun that was destined to stick around. New for 2026, Black Hills is adding another projectile to their 6mm ARC lineup featuring a newly designed bullet from Sierra: the Black Hills 107 Grain Sierra MatchKing X.
The new load provides the accuracy and exceptional long-range capability of the established MatchKing line, but with the superior terminal performance needed in a hunting bullet.
Testing of this load provided wound diameters of 7 inches and retained projectile weight necessary for deer-sized game, even at close-range impact velocities.
With the selection of projectiles available from Black Hills, the 6mm ARC is a great choice for antelope and deer at moderate ranges, especially for the recoil-sensitive, younger shooter.
At its core, the 6mm ARC cartridge fits and functions nicely in an AR-15 platform and with a reasonable magazine capacity. Perceived recoil is similar to the 5.56, and accuracy capability is extremely good.
The 6 ARC utilizes heavier, higher BC (ballistic coefficient) bullets than the 5.56. The 6 ARC also has more power and longer-range capability.
Black Hills' 90-grain Dual Performance ammo loaded with a monolithic fragmenting bullet made by Lehigh Defense has proven devastating on everything from prairie dogs and coyotes to antelope and mule deer.
