.358 Win. Subsonic

The .358 Winchester is a powerful, large-bore cartridge that can be effectively adapted for subsonic use, offering excellent terminal performance at low velocities due to its larger caliber and heavy bullet compatibility. Based on the .308 Winchester case necked up to accept .358 caliber bullets, it retains the same case capacity and pressure characteristics, which poses both advantages and challenges for subsonic reloading.

The .358 Win is particularly well-suited for subsonic applications because of its ability to stabilize and launch heavy bullets — typically in the 200 to 310 grain range — at subsonic speeds while maintaining effective energy on target. Common bullet choices for subsonic loads include the 250gr Hornady RN, 280gr cast bullets, or specialized expanding subsonic projectiles like those from Lehigh Defense or Maker Bullets.

Fast-burning powders such as Trail Boss, IMR 4227, or Hodgdon H4895 (with appropriate reduced load data) are often used to safely fill the case while avoiding erratic ignition. Because of the case volume, attention must be paid to powder position sensitivity, and some reloaders use inert fillers (carefully) or opt for bulky powders like Tin Star to improve consistency.

The .358 Win benefits from a barrel twist rate of 1:12 or faster to stabilize heavy bullets at subsonic speeds, with 1:10 being ideal for 280–300 grain projectiles. Suppressed .358 Win rifles produce a deep, low-frequency report, and due to the bullet’s large frontal area, even subsonic loads can generate reliable expansion or significant energy transfer, making this cartridge effective for close-range hunting of medium to large game.

Overall, the .358 Winchester is one of the better large-bore choices for subsonic shooting, particularly when power and quiet operation are both desired. It offers a rare combination of suppressed performance and stopping power in a relatively compact cartridge.