The .300 Weatherby Magnum is a powerful, high-velocity .30-caliber magnum cartridge introduced in 1944. One of the flagship Weatherby cartridges, it delivers more velocity than standard .300 magnums and is valued for hard-hitting performance on large game at long range.

The .300 Weatherby Magnum was introduced in 1944 and became one of the cornerstone cartridges of the Weatherby line. It was designed to push .30-caliber bullets faster than the standard .300 magnums of its era, embodying Roy Weatherby's core belief in the advantages of high velocity for flat trajectory and energy on game. Ballistically the .300 Weatherby fires .30-caliber bullets — commonly 150 to 200 grains — at very high velocity, exceeding the standard .300 Winchester Magnum and delivering a flat trajectory with high retained energy suitable for large game at extended range. That performance is matched by heavy recoil and muzzle blast, placing it among the harder-recoiling .30 magnums and rewarding a well-fitted rifle and practice. Among the .30-caliber magnums it occupies the high-velocity tier — distinct from the standard .300 Win Mag in pushing more speed, and from the modern .300 PRC in predating the design-around-heavy-bullets approach. It has a long, established following for big-game hunting, particularly where reach and energy on large animals are priorities. Today the .300 Weatherby Magnum is used for big-game hunting and long-range target shooting, with availability centered in Weatherby and other rifles plus established ammunition support. Its combination of high .30-caliber velocity and long-range energy is why it has remained a flagship magnum for big-game hunters.

General information about this caliber — not a recommendation for this specific firearm.