The 7x57mm Mauser (.275 Rigby)
By Chuck Hawks
Illustration courtesy of Hornady Mfg. Co.
The 7x57 was developed by the famous German firm of Mauser in 1892, and adopted by the Spanish government in 1893. Subsequently, several Latin American countries adopted the 7x57, including Mexico. In Europe, Serbia adopted the cartridge, and it became a popular sporting cartridge all over Europe. In Great Britain the 7x57 became so popular that the John Rigby Company adopted it as the .275 Rigby. Many bolt action rifles built in the UK were so marked. Under both names the cartridge was used extensively for plains and mountain game in Africa and Asia. Ammunition is manufactured and sold in Europe, Africa, North America and most
of the world. The 7x57 is a true world-wide cartridge.
W.D.M. Bell, perhaps the most famous of all African commercial ivory hunters, killed the majority of his over 1000 elephants with the 7x57. He used the 175 grain FMJ bullet for brain shots, and liked the .275 Rigby (as he called the 7x57) for its accuracy and low recoil and report.
Current ammunition catalogs from PMC, Remington and Federal show loads for the 7x57
with 140 grain spitzer bullets (SD .248) at a muzzle velocity (MV) of 2,660 fps and muzzle energy (ME) of 2,199 ft. lbs. Winchester loads a 145 grain spitzer to the same MV for a ME of 2279 ft. lbs. Federal and PMC also load 175 grain RN bullets at a MV of 2440 fps and ME of 2315 ft. lbs. These are the standard American low pressure factory loads.
Here are some 7x57 specifications that should be of interest to reloaders: bullet diameter .284", maximum COL 3.065", maximum case length 2.235", MAP 46,000 cup.
There are a wide variety of 7mm bullets available to the reloader, from around 110 grains to 195 grains. Barnes offers a 175 grain RN solid (SD .310) and a 195 grain soft point spitzer bullet (SD .345). The North American shooter who wants to get maximum utility out of a 7x57 really should be a reloader. The 130-140 grain bullets are generally the best choice for CXP2 class game, while the 150-175 grain bullets get the nod for CXP3 class game. Restrict shots at the latter to 200 yards/meters or less.
The 7x57 is a well balanced and well designed cartridge for which a number of medium burning rate rifle powders are appropriate. Among these are H414, H380, H4350, IMR 4064, IMR 4320, IMR 4350, and W760.
The reloader with a strong rifle who loads to about 50,000 cup can do better than most factory loads. Do not use the maximum loads quoted below in the relatively weak Model 93 and 95 Mauser actions, or in Remington rolling block rifles. According to the Speer No. 13 Reloading Manual the Speer 130 grain spitzer bullet (BC .394, SD .230) can be driven to 2649 fps by 46.0 grains of H414 powder, and 2960 fps by a maximum load of 50.0 grains of H414.
The 145 grain Spitzer (BC .457, SD .257) can be driven to 2501 fps by 44.0 grains of H414, and 2748 fps by a maximum load of 48.0 grains of H414.
The 160 grain spitzer (BC .502, SD .284) can be driven to 2,363 fps by 42.0 grains of H414, and 2582 fps by a maximum load of 46.0 grains of the same powder. All of the above loads used Remington cases and CCI 250 primers, and were chronographed in a 22 inch rifle barrel.
Note: A full length article about the 7x57 can be found on the Rifle Cartridge Page.