Paul Mauser's Model 1888 rifle was really a modified Mannlicher, not as stout as the Mauser that replaced it a decade later. But Mauser's name has long been attached to the 7.9x57 cartridge that appeared in 1888 for the "Gewehr 88," or "Commission" rifle. (The 1888 rifle owes its design to the German Infantry Board, or Commission at Spandau Arsenal). The 226-grain round-nose 7.92mm bullet at 2,093 fps flew as flat as its contemporaries: the 210-grain paper-patched bullet of the 7.5x55 Schmidt-Rubin at 1,970 fps, the 215-grain .303 British bullet at the same speed (cordite load), the 220-grain smokeless load for the .30-40 Krag that clocked over 2,100. Now conveniently called the 8x57, the original cartridge fired a .318 bullet. In 1905 the Germans reconfigured the case to hold a .323 (8mm) bullet.
The first .323 bullet for the 8x57 was relatively lightweight, a 154-grain spitzer driven a sizzling 2,880 fps. Rifles and ammunition made after the change carry an "S" designation. The earlier .318 rifles and ammo bear an "I" or "J" for Infanterie (the German I and J can be used interchangeably). So S or JS cartridges can be fired safely only in the later rifles. I and J ammo is safe but inaccurate in post-1905 bores.
In some ways the 8x57 spurred development of infantry loads for the U.S Army. By the 1890s, as Paul Mauser refined his turn-bolt mechanisms, Germany's 8mm J cartridge had become solidly established. Its counterpart, our .30-40 Krag, would serve ably in the Spanish-American War. But Mauser's 1898 action upstaged the Krag-Jorgensen, a costly rifle and one that couldn't match the Mauser for strength. Also, the advantages of rimless cartridges were becoming apparent.
The Model 1903 Springfield fired a .30-caliber rimless cartridge that headspaced on the shoulder, like the 8x57 Mauser. Powder capacity and operating pressure exceeded the Krag's. The .30-03's 220-grain bullet at 2,300 fps matched the 8x57 ballistically. When the Germans changed their cartridge in 1905, the Americans scrambled to introduce the "Ball Cartridge, Caliber .30, Model 1906." It launched a 150-grain bullet at 2,700 fps. For some reason the case was shortened .07, to .494. Consequently, .30-03 chambers were long for the new round. All .30-03 rifles were recalled and rechambered to .30-06.
The 8x57 proved as deadly in battle as the .30-06 and as versatile in the field. But in the wake of World War II, few Americans favored the 8x57. Some hunters bored surplus 1898 Mausers to 8mm/06. More rebarreled them or, if they couldn't afford a Winchester 70, opted for a Springfield. Whether battle memories or something else tainted their preferences, sportsmen Stateside still dismiss the 8x57. A pity!
In my youth, the 8x57 was recommended for deer and black bears. In truth, it's got enough sauce for much bigger game. It suffers from a dearth of suitable loads. European ammo makers RWS and Norma do the round justice with tough bullets revved up. Surely, this old cartridge can do more than we in the U.S. have allowed. If the .30-06 had been accorded so little development, it, too, would seem anemic. Operating pressure for this round is 53,000 psi. Standard rifling twist in 8x57 rifles: 1:9.5.
A 170-grain 8mm softpoint loaded to 2,250 fps in the U.S. loses enthusiasm quickly. But Norma catalogs three 196-grain 8x57 loads starting at 2,526--as fast as a .308 hurls 180s. The rimmed version of this cartridge (for hinged-breech guns) survives; Norma offers four loads, the 196-grain bullets clocking about 130 fps less than in the rimless line. RWS has four each of potent rimless and rimmed 8x57 loadings, plus a "JR" option. Stateside, Winchester's Super X 170 Power Points and Remington's 170 Core-Lokts deliver near-identical--and distinctly unexciting--payloads and trajectories. This cartridge can be hand-loaded to higher performance levels in strong bolt rifles. The pointed or semi-pointed bullets now available extend effective range dramatically. With proper bullets, the 8x57 is surely an elk round, superior to the .300 Savage, which has killed many elk. The 8x57 is best in mid-length actions. It's too long for .308-length actions; in a .30-06 receiver, you might as well have a .30-06 or .338-06.