The 8x57JS (8mm Mauser)
By Chuck Hawks
This is the cartridge with which Germany fought two world wars. The cartridge, officially designated the M/88, and the Commission rifle to shoot it, were adopted by the German Army in 1888.
The civilian designation for the 1888 load is 8x57J. (8mm is the bullet diameter, 57mm is the length of the case, and J stands for infantry in German.) This cartridge fired a round nose 227 grain bullet of .318 inch diameter.
In 1905 the cartridge was revised, and a 154 grain spitzer bullet of .323 inch diameter was adopted for the new, much stronger, Model 98 Mauser rifle. This new bullet was given a MV of about 2,800 fps and greatly extended the lethal range of the 8mm Mauser, which was now called the 8x57JS (the S stands for spitzgeschoss, from which came the Americanized term "spitzer").
The advent of the 8x57JS caused the U.S. Army to revise its new .30-03 service round and introduce the .30-06. The 8x57JS became one of the most popular cartridges in Europe, and ammunition is available worldwide. Everywhere, except in North America, it is considered one of the great all-around cartridges.
The 8x57 uses a modern style rimless case with moderate body taper and a shoulder angle of a little less than 21 degrees. The rim diameter is .473 inch, the same as the 7x57. The case is 2.24 inches long, and the overall cartridge length is 3.25 inches. The C.I.P. (European) standard maximum presure for the 8x57JS is 49,347 cup. In the U.S. the SAAMI maximum average pressure is limited to only 37,000 cup.
In the U.S., 8x57 factory loads have always been under-loaded. This pretty well emasculated the cartridge's performance and ensured that it would never become very popular in America. This was done because the original 1888 German Commission rifle could not withstand the higher pressures of 8x57JS loads intended for use in the strong Mauser 98 action. Evidently the U.S. loading companies didn't want to bother informing American shooters about the differences between the two cartridges and the rifles that shoot them.
The problem in the U.S. has been exacerbated by the importation of many surplus military rifles of indifferent quality, some sold with bolts scavenged from other rifles. Typical American factory loads for the 8x57 give a 170 grain bullet a MV of 2,360 fps and ME of 2,102 ft. lbs. European companies load a 165 grain spitzer bullet to about 2,859 fps and 2,965 ft. lbs. of energy.
For the reloader with a sound Mauser 98 rifle, these problems and limits can be ignored, and the 8mm Mauser becomes a cartridge comparable to the .308 Winchester and .30-06 Springfield. Bullets from 125 to 220 grains are available.
The Speer Reloading Manual No. 13 lists loads up to 50,000 cup for quality 8x57JS rifles. These give the Speer 150 grain spitzer bullet (BC .369, SD .205) a MV of 2695 fps with 47.0 grains of IMR 4064 powder, and up to 2,915 fps in front of 51.0 grains of IMR 4064 powder. A 150 grain spitzer would be my choice for hunting deer and general CXP2 class game.
The trajectory of the 150 grain bullet at 2900 fps looks like this: +2.6 inches at 100 yards, +3 inches at 135 yards, +1.9 inches at 200 yards, -3 inches at 280 yards. So loaded, the 8x57 becomes a 280 yard deer, antelope, sheep, and goat cartridge.
The Speer 170 grain semi-spitzer (BC .354, SD .232) can be driven to a MV of 2509 fps by 45.0 grains of IMR 4064 powder, or a MV of 2,723 fps with a maximum load of 49.0 grains of IMR 4064. For most CXP3 class game a 170 grain bullet at a MV of about 2650 fps (ME 2551 ft. lbs.) seems like a good choice.
The Speer 200 grain spitzer bullet (BC .411, SD .274) can be driven at a MV of 2196 fps by 42.0 grains of IMR 4064, or to a muzzle velocity of 2434 fps with 46.0 grains of IMR 4064 powder. A 200 grain bullet at 2400 fps should do for the largest game for which the 8x57 is suited. All of these Speer loads used Remington brass and CCI primers; velocities were taken in a 24 inch barrel.
Copyright 1999, 2012 by Chuck Hawks. All rights reserved.