8mm Mauser (8x57) Handloading Tips

In many parts of the world, the 8mm Mauser prospers in the same performance niche where we place the .30-06. Sadly, as loaded in the United States, it is like a rejected calf: weak, underperforming, and failing to thrive.

In Europe and North America, then-new military cartridges of roughly .30-caliber that appeared between 1888 and 1892 shared common attributes. All had long FMJ-RN bullets weighing from 215 to 227 grains and posted muzzle velocities in the ballpark of 2,000 to 2,200 fps, including the 8mm Mauser cartridge.

Dating to1888, it is among the oldest smokeless-powder service cartridges and among the first with a rimless case. Reacting to the French 8x50R Lebel cartridge, the Germans developed Commission Model 88 repeating rifles using 8x57mm smokeless ammo when the U.S. Army was still issuing single-shot M1884 Springfields and blackpowder .45-70 ammunition.

According to Mauser historian Ludwig Olson, the German entry was officially the 7.9x57mm in military circles but was called the 8x57mm in sporting use. Current European barrel specifications for the 1888 version show a bore diameter (land to land) of 7.8mm (0.3070 inch) and a groove diameter of 8.07mm (0.3177 inch). About 1905, an improved version saw the bore diameter increased to 7.89mm (0.3106 inch) and groove diameter to 8.2mm (0.3227 inch).

Ammo for older rifles with 0.318-inch bores was marked “I.” 1905 ammo for newer rifles was “IS.” The “I,” said to stand for the German word “Infanterie,” was somehow transcribed as “J” in English—8x57J and 8x57JS. The “I” is still used in some ammo catalogs and on official cartridge/chamber drawings promulgated by C.I.P. (the European equivalent of SAAMI).

Olson explains the “S” suffix that began with the improved 1905 loading, saying the “S” was for Spitzgeschoss, German for “pointed bullet.” It inspired our term “Spitzer.” The diameter change was incidental.

Germany issued the upgraded “IS” version to troops in 1905, when U.S. .30-40 Krags were still abundant in many American units. The robust Model 98 Mauser action gave the Germans an advantage, permitting cartridges of higher pressure than feasible in weaker Krag or Lee-Enfield bolt rifles.

Quoting Olson’s data again, the 1905 German ammo upgrade took advantage of that strong rifle. A 154-grain Spitzer achieved over 2,900 fps from the standard German 740mm (29.13-inch) rifle barrel and 2,850 from a 600mm (23.6-inch) carbine. That is slightly better than the very similar 1906 version of the U.S. Caliber 30 service cartridge, which was estimated to have done 2,700 fps from a 24-inch barrel.

About 1916, the Germans again followed the French, adding a long-range load having a 197-grain Spitzer boattail FMJ at 2,575 fps (740mm barrel). That’s on par with top .30-06 handloads with modern 200-grain bullets, although from a longer barrel.

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U.S. industry specs for the .30-06 put the maximum average pressure (MAP) at 60,000 psi. Traditional velocity recommendations are 2,790 to 3,000 fps with a 165-grain bullet and 2,540 fps with a 200-grain bullet (24-inch barrel). RWS shows current 8mm Mauser ammo with a 160-grain bullet at 2,720 fps and a 198-grain bullet at 2,540 fps (22.8-inch barrel). That’s too close to call for practical hunting needs.

Further pressure evidence came from my ballistic tech, who ordered some Turkish 8mm military ammo loaded in the 1950s. On our crusher barrel, it posted right on 50,000 CUP, the crusher MAP for .30-06.

Differences in the physical location of pressure sensors mean we can’t directly convert European pressure limits to SAAMI values. However, they can be compared. The C.I.P. MAP for the 8mm Mauser is 3,900 bar. The same standards have the .30-06 at 4,050 bar. SAAMI is 60,000 psi. A quick math comparison says the 8mm’s Euro standard is almost 58,000 psi on the SAAMI system.

If military 8mm Mauser ammo and most modern European sporting ammo have near-parity with the vaunted .30-06, what happened to the 8mm Mauser in the U.S.? We could say, “The pressure got to it.”

U.S. specs for the 8mm Mauser recommend a 170-grain bullet at 2,340 fps at only 35,000 psi MAP from a 24-inch barrel. That’s only marginally better than the .30-30 fired from a much shorter barrel (20 inches).

Such a meager pressure limit reflects a dimensional issue: an 8mm Mauser cartridge can be potentially chambered and fired in America’s most common centerfire rifle chamber, the .30-06, putting a 0.323-inch bullet in a 0.308-inch hole with significant gas escape.

This is crippling unless you are a handloader. Assuming the rifle is capable, the handloader can recreate European performance. As of last check, Hodgdon, Hornady, and Speer show handloads taken close to 50,000 CUP or 60,000 psi.

Obviously, the rifle is everything. Nothing less than a Model 98 Mauser will do. I know a fair bit about Mausers but do not consider myself an expert. Have a real expert check the overall condition, including the manufacturer code and date on military models; I am leery of some of the lower-quality arsenals with late World War II dates.

If the number on the bolt does not match the number on the receiver, don’t shoot the rifle without a headspace test. Too many imported war-surplus Mausers had their bolts removed for shipping, and no one bothered to make certain the proper parts were reunited.

Hodgdon’s online reloading data shows excellent velocity with 150- and 170-grain bullets from CFE 223 propellant. In general, mid-rate propellants that work well in the .308 Winchester do fine in the 8mm Mauser.

Speer’s 200-grain 0.323-inch Spitzer Hot-Cor was designed expressly for the 8mm Remington Magnum. I suspect that within 200 yards, it should expand from an 8mm Mauser rifle without issue. Its magnum-spec jacket should give deep penetration. With 195- to 200-grain bullets, propellants in the 4350 category start to be useful.

With prudent handloading, the 8mm Mauser is still a very useful cartridge for non-dangerous North American game, just as it was for European sportsmen and African colonials for well over a century.