The 6.5×53mmR, originally and more correctly produced as the 6.5×53.5mmR, and in imperial system nomenclature known as the .256 Mannlicher, is a late 19th-century rimmed centerfire military rifle cartridge similar to other early smokeless powder designs.

[3] Dutch ammunition with cartridge cases made of brass (pre-occupation) or steel (under German occupation) may be encountered on the American surplus market.

In both instances, the primer pocket is Berdan-style, of an unusual type (Roth-patent), and features a central flash hole running through the center of the integral Berdan anvil.

The empty clip will fall out through a hole in the base of the magazine housing when out of cartridges, enabling quick reloading of the rifles during combat.

[13] Additional case dimensions Based on direct measurement of Dutch and German unfired ammunition averaged and compared to published original sources:[14][15] Surplus WW2 and earlier ammunition is still available on the collector market, but these are primarily corrosive in nature and rifles fired using it will require a thorough cleaning to reduce the development of rust.