7×57mm Mauser

The 7×57mm Mauser was Paul Mauser’s rimless, bottlenecked smokeless cartridge for the Model 1892/93 Mauser rifles, adopted first by Spain and then by a run of Latin American, Balkan and other export customers through the 1890s and 1900s. Its case shape — a fairly long, gently tapered body over a full-diameter rim-free head — became the template Mauser reused, resized, for most of the family of military rounds that followed it.

Its combat record is disproportionate to how obscure the cartridge is today. Boer commandos carrying Mauser rifles in 7×57mm inflicted heavy losses on British forces at long range during the Second Boer War, an experience credited with pushing Britain toward the flatter-shooting, smaller-calibre rounds and improved marksmanship doctrine that shaped its rifles for decades afterward. The cartridge also had a long career as a sporting round, marketed in Britain by John Rigby & Co. under the name “.275 Rigby” and used by hunters including W. D. M. Bell on dangerous game, on the strength of its flat trajectory and moderate recoil for a military-era cartridge.

This entry’s dimensions and pressure are transcribed from the C.I.P.’s TDCC datasheet. Its three RWS-branded loads (KS, ID Classic, HMK) are transcribed directly from RWS’s own archived ballistic-data page, including each bullet’s published ballistic coefficient — and that page states a 600 mm test barrel for every one of them, not the 735 mm the Wikipedia infobox states generically for “RWS” loads on this cartridge; the archived primary source is followed here. A fourth, unbranded “factory military” 173-grain loading is carried as estimated rather than verified, because no manufacturer or archival source for it beyond the Wikipedia infobox itself was found. The SAAMI pressure figure the infobox cites points at a dead link and is not recorded.