.350 Mag. Rigby Load Data & Reloading Guide

The .350 Mag. Rigby, developed in 1912 by the British rifle maker John Rigby & Co., was designed as a proprietary cartridge for their bolt-action rifles. This caliber emerged during a period when British gunmakers were innovating with new magnum cartridges to cater to demanding hunting expeditions in Africa and Asia. It was primarily intended for hunters seeking a powerful medium-bore cartridge capable of taking down large and dangerous game.

Technically, the .350 Mag. Rigby is a rimless, bottlenecked cartridge. It typically features a case length of about 2.87 inches and operates at high pressures similar to other magnum cartridges of its time. This caliber generally supports bullet weights ranging from 225 to 300 grains, with 250-grain bullets being particularly popular due to their balance of velocity and energy, providing effective performance on game such as lions and large deer.

Ballistically, the .350 Mag. Rigby delivers impressive performance with muzzle velocities typically ranging from 2,500 to 2,800 feet per second. This ensures sufficient energy retention and penetration for successful hunting at medium ranges. Its flat trajectory and stopping power make it an ideal choice for hunters in pursuit of large game across diverse environments, from dense forests to open savannas.

For reloaders, the .350 Mag. Rigby presents significant advantages due to its historical prestige and practical capabilities. Though factory ammunition can be rare, custom reloading offers opportunities to tailor loads to specific hunting needs. The experienced reloader can optimize bullet weight and powder charge combinations to achieve desired performance characteristics, making the .350 Mag. Rigby a versatile and rewarding caliber for those skilled in the art of ammunition reloading.