The Hornady Subsonic Rifle Ammo 338 ARC 307 gr Sub-X delivers a purpose-built load for shooters who run suppressed rifles or hunt where reduced report and reliable terminal performance matter, using Hornadys Sub-X bullet design that pairs a lead core, cannelure for positive crimping in semi-autos, and long grooves in the gilding metal jacket with a patented Flex Tip to promote controlled expansion even at subsonic velocities. With a 307-grain Sub X projectile moving at roughly 1,050 fps and producing about 752 ft-lbs of energy, this round offers heavy-for-caliber momentum and deep penetration potential for medium to large game at closer ranges, while minimizing disturbance on the shot to aid follow-up shots and preserve situational awareness in the field. The brass-cased rounds feed and extract smoothly in modern magazines and the Sub-X profile works well in barrels and suppressors where consistent bullet shape and the cannelure aid reliable seating and cycling. If you run a 338 ARC platform and want a quiet, controlled-velocity option for woodland or thicket hunting, tactical practice with signature reduction, or dedicated suppressed range work, this Hornady Subsonic load provides a serious, purpose-driven choice.