.375 Weath. Mag. Load Data

The .375 Weatherby Magnum is an iconic cartridge well regarded among enthusiasts of big-game hunting and ammunition reloaders alike. Introduced in 1944 by Roy Weatherby, the cartridge was designed during a period of intense innovation in rifle and cartridge development. It is essentially a “blown out” and slightly improved version of the legendary .375 H&H Magnum, a cartridge that had already established itself as a standard for hunting large and dangerous game across the globe. By increasing the shoulder angle and expanding the case capacity, Weatherby engineered the .375 Weatherby Magnum to achieve higher velocities and better performance at long ranges than its predecessor. While it initially gained attention among American hunters and African safari goers, over time, it has become a favorite among reloaders seeking a cartridge that offers a balance of power, accuracy, and reloadability.

When it comes to practical applications, the .375 Weatherby Magnum is famed for its versatility in big-game hunting scenarios. Its powerful ballistics make it ideally suited for pursuing the largest and most dangerous animals on all continents. The cartridge’s improved case design and increased powder capacity yield higher muzzle velocities compared to the original .375 H&H, translating into better terminal performance and a flatter trajectory. Reloaders find it particularly useful for customizing loads tailored to specific hunting conditions, from the dense brush of North America to the open plains and thick bush of Africa. Whether stalking moose in Alaska or facing the formidable Cape buffalo in Africa, the .375 Weatherby Magnum’s power and dependability make it a trusted companion for hunters who prioritize both stopping power and accuracy.

Target species for the .375 Weatherby Magnum typically include some of the most challenging and resilient animals found worldwide. Renowned for its effectiveness on the entire spectrum of dangerous game, it is suitable for African “big five” species—lion, elephant, rhino, leopard, and especially Cape buffalo—as well as North American favorites like brown bear, moose, and bison. The cartridge’s ability to deliver deep penetration and massive energy transfer ensures humane and ethical kills, even on thick-skinned or heavily muscled game. Reloaders can adapt their bullet choices and powder charges to match the demands of each species or hunting environment, taking advantage of the cartridge’s flexible performance profile. This customization is incredibly valuable when hunting internationally, where legal requirements or local traditions may dictate minimum caliber or energy thresholds for dangerous game.

Typical bullet weights available for the .375 Weatherby Magnum range from 235 grains up to 300 grains, with the 270- to 300-grain range proving most popular among reloaders seeking optimal penetration and energy for large game. The 300-grain bullet, in particular, is a staple for dangerous game hunting, offering a great balance between sectional density and retained energy downrange. Muzzle velocities can vary significantly depending on bullet weight and handload selection, but the .375 Weatherby typically pushes a 300-grain bullet past 2,600 feet per second, generating in excess of 4,500 foot-pounds of muzzle energy. The cartridge features a belted, bottleneck case design, allowing it to be safely used in rifles originally chambered for the .375 H&H, though Weatherby-chambered rifles will maximize its ballistic potential. For reloaders, the high case capacity offers room for a variety of powder choices, and the broader selection of premium .375-caliber projectiles on the market ensures that each handload can be tailored to specific needs, whether for maximum penetration, expansion, or long-range accuracy.