What is weight difference between .325 WSM and .308 Win ammo?

Ammunition Comparison

When comparing .325 WSM and .308 Win cartridges, it’s essential to consider their design and application. The .325 WSM (Weatherby Magnum) is a high-powered cartridge designed for long-range hunting, particularly for large game like elk. Its heavier bullet weight and increased case capacity allow for a flatter trajectory and greater kinetic energy at longer ranges.

Optimal Loadings

For elk hunting, ideal loadings for .325 WSM cartridges typically involve a heavy, high-BC bullet (0.5-1.0 G1) with a minimum of 240 grains. Weatherby’s own .325 WSM loadings, such as the 250-grain Barnes Triple-Shock X, deliver impressive performance. In contrast, .308 Win cartridges often feature lighter bullets (150-180 grains), which, although effective at closer ranges, may not provide the same level of penetration and expansion at longer ranges.

Ballistic Performance

The increased weight and case capacity of .325 WSM cartridges result in improved ballistic performance. At 400 yards, a .325 WSM cartridge with a 250-grain bullet can retain around 1,300 ft-lbs of kinetic energy, whereas a .308 Win cartridge with a 180-grain bullet may only retain around 700 ft-lbs. This significant difference in kinetic energy makes .325 WSM cartridges better suited for long-range elk hunting, where a clean, one-shot kill is often the goal.