9.3 x 66 Sako (370 Sako Mag) Load Data

The 9.3 x 66 Sako, also widely recognized as the .370 Sako Magnum, is a relatively modern rifle cartridge with a storied Finnish heritage. Developed by Sako Ltd. in the late 1990s, the cartridge was introduced as an answer to the need for a powerful, yet manageable, medium-bore magnum for European big game hunting. Its design was based on the .375 H&H Magnum case, shortened and necked down to accept the specific 9.3mm (.366) diameter bullets commonly favored in Europe. The objective was to complement the performance of established cartridges like the 9.3x62mm Mauser but provide a step up in power and reach, especially in open country or when targeting tougher game. While it initially found popularity in Finland and other Scandinavian countries, the 9.3 x 66 Sako has also seen growing interest among reloaders and hunters worldwide.

The primary application of the 9.3 x 66 Sako centers on hunting large and dangerous game, making it highly regarded for moose, bear, wild boar, and red deer in Europe. Its magnum velocity and energy levels allow it to excel in challenging environments, where reliable stopping power on big-bodied game is critical. In Africa, where it is permitted by local regulations, the cartridge is an excellent choice for plains game and sometimes even for thick-skinned dangerous species, standing as an alternative to other classic Magnums. The versatility of the 9.3 x 66 Sako is further enhanced by its relatively moderate recoil compared to larger magnums, allowing skilled shooters to maintain accuracy during rapid follow-up shots. Its adeptness at long-range shots, without sacrificing terminal ballistics at closer distances, is a particular advantage for experienced reloaders seeking a do-it-all big game cartridge.

When discussing the target species for the 9.3 x 66 Sako, it is clear this cartridge was specifically conceived for those hunting the most formidable European and African game. In its home continent, the cartridge’s power is more than sufficient for Scandinavian moose, wild boar in dense forests, and large red stag. Hunters have also employed it with success on brown bear, where deep penetration and robust bullet construction are essential. Additionally, the cartridge is legal for most African safari game, particularly for eland, kudu, water buffalo, and other large-bodied antelope, expanding its target spectrum. Its impressive performance on heavy animals is a testament to its bullet diameter and energy, both critical parameters for ethical hunting.

For reloaders, one of the most appealing aspects of the 9.3 x 66 Sako is the diverse selection of bullet weights available for tailoring performance. Typical factory and reloading options include bullets from 232 grains up to 285 grains, with the 250-286 grain range being the most popular due to its optimal balance of velocity, trajectory, and terminal effect on large game. Heavier bullets deliver deep penetration needed for thick-skinned or heavy-boned animals, whereas lighter projectiles can be useful for flatter trajectories and less recoil. The cartridge’s case capacity enables it to generate muzzle velocities in the 2500–2650 fps range with most bullet weights, producing energies well above 3500 ft-lbs. This combination of velocity and energy, delivered by the 9.3mm projectile, ensures that reloaders can achieve tailored loads for specific hunting scenarios. Characteristics like moderate recoil, excellent accuracy, ballistic efficiency, and reliable feeding in bolt-action rifles further solidify the 9.3 x 66 Sako as a prized choice among experienced reloaders and big game hunters worldwide.