6.5 x 58 mm Mauser Port. Load Data & Reloading Guide

The 6.5 x 58 mm Mauser, also known as the 6.5 x 58 mm Mauser Portuguese, emerged in the early 20th century when Portugal sought to modernize its military small arms. This caliber was adopted for use in the Portuguese Vergueiro rifle, which was a modified design incorporating aspects of the German Mauser system. Initially introduced in the late 1890s and remaining in use through World War I, this cartridge is notable for its role in both military and sporting applications.

Technically, the 6.5 x 58 mm Mauser features a rimless, bottleneck case design that allows for smooth feeding and extraction from bolt-action rifles. The casing measures 58 mm in length, tailored to accommodate projectiles that range anywhere from 140 to 160 grains, a common weight class for cartridges in this caliber. Standard factory loads typically push a 156-grain bullet around 2,500 feet per second, offering a balanced mix of velocity and impact energy suitable for mid-sized game hunting.

Ballistically, the 6.5 x 58 mm Mauser delivers flat-shooting trajectories alongside manageable recoil, characteristics appreciated among hunters targeting deer-sized game at moderate ranges. Its high sectional density enables deep penetration, making it effective for ethically taking larger game under the right conditions. While its military usage has waned, it remains a cartridge appreciated by collectors and custom rifle enthusiasts.

For reloaders, the primary advantage of the 6.5 x 58 mm Mauser lies in its less mainstream status, providing an opportunity to create tailor-made loads specific to niche requirements. Reloaders can experiment with different powder types and bullet weights, optimizing ballistic performance to fit their needs. Additionally, reloading extends the life of this cartridge, which can occasionally be challenging to source, preserving the usability of historic rifles chambered for it.