format_quoteIn the mid-1880s, Peter Paul von Mauser designed the 8×57mm for the Commission Model-1888 Rifle. Original cases were derived from a Swiss blackpowder round. Mauser converted those to a 57-mm long, rimless, bottlenecked design. The original load used a 226-grain round-nosed bullet of 0.318-inch diameter.
It was soon discovered the primitive and highly erosive smokeless propellant of that era resulted in short barrel life with the shallow rifling originally used. All Military rifles were recalled and the rifling was recut to increase groove depth. This alteration increased groove diameter from 0.318 to 0.323-inch. In 1905, a new, 154-grain Spitzer load was developed for this version. This bullet had a surprisingly high BC and was launched much faster using an improved propellant that was more efficient and less erosive.
Sporting rifles chambered for the 8mm and made with the original 0.318-inch groove diameter still exist. These are sometimes used. If you have an antique sporting rifle chambered for the 8mm Mauser, do not shoot it with any load using the 0.323-inch bullet until you prove it has 0.323-inch groove diameter.
After WW-I, when the 154-grain load had been proven ineffective against light armor beyond a few hundred yards Germany replaced it with the anti-aircraft load using a 196-grain Spitzer bullet loaded at about 2700 fps when fired from the 29.1-inch long barrel of the Gewehr-98 and about 2600 fps when fired from the 23.6-inch barrel of the M-98. In either rifle, performance of this load far outclassed the 30-06 Military load. Interestingly, BC of this bullet is essentially the same as modern 8mm match bullets of similar weight made by Nosler and Hornady. This makes it easy to duplicate performance of the original military load.
When loaded in a modern rifle in good condition and taking advantage of the CIP pressure specification, the 8mm Mauser is ballistically extremely similar to an enlarged 308 Winchester. It has 10% greater cross-sectional bore area and just about 10% greater case capacity. The only deficit is the pressure difference, the 8mm works at about 10% less pressure. A 2-inch difference in barrel length will just about make up for the pressure difference. As such, in a gun with a 24-inch barrel, the 8mm will launch 10% heavier bullets at about the same velocity compared to what a 22-inch barreled 308 Winchester will do. The same propellants work equally well in both cartridges. This means the 8mm Mauser is just as easy to work with as the 308 Winchester is.
There is also a rimmed version, the 8×57mmR, as with many European chamberings. Generally, the rimmed version should be loaded to significantly less pressure out of due respect for the nature of the guns chambered for such rounds.
Considerable name confusion among the various versions of the 8mm Mauser exists. Much of this started with U. S. Military Intelligence Agents misreading the ornate German script “I” (for Infantry) as a “J” in documents captured during WW-I, when the U. S. was trying to understand why the 8mm had such phenomenally superior performance. Bore diameter was about 0.311-inch, which is 7.9-mm, which explains why this round is sometimes referred to as the 7.9mm Mauser — just one more thing adding to the confusion of names describing the same cartridge.
In hindsight, the explanation for the ballistic advantage was not complicated: use of better propellant resulted in better ballistics. The same still holds. For example, with the best propellant now available, I can load my original 30-06 Springfield to launch the 210-grain Nosler AB-LR bullet at 2700 fps without exceeding SAAMI specification pressure; as such, compared to the original Military load, I am launching a 40% heavier bullet at the same velocity, essentially 100% of that advantage results from improved propellant efficiency.
The diamond-cut sheet propellant Germany used in the early 1900s was not quite as good as the best propellants we have today but it was close. Use of propellants of that type fell out of favor for one simple reason: the system required to manufacture those propellants involved significant mechanical handling. That required more motors, more bearings, and more powered devices overall. Each of those was a heat source; and, each was a potential source of a spot hot enough to ignite the inevitable propellant residue that would accumulate. Predictably, this combination of factors resulted in the all-too-common disappearance of propellant factories.
Internet claims and published data for the 154-grain Military load is 2880 fps, fully 135 fps shy of what WW-I era Military ball ammo demonstrated when tested in the longer barrel of the original Gewehr-98 rifles. In 1976, testing of original WW-I era ammo proved what the 154-grain Military load would do. Samples from two of three sealed containers of two production lots were tested for accuracy and velocity using three unissued Gewehr rifles.
Average muzzle velocity was 3015-fps with near-MOA average accuracy for three-shot, 100-yard groups fired from each rifle using the original iron sights.
The most accurate gun was in the middle of the three for velocity. It shot three bullets from one of the production lots consistently into less than 1¼-inches at 100 yards. Every combination of rifle and ammo put three-shots inside 1½-inches at 100 yards.
The slowest shooting gun was within 30 fps of the fastest-shooting gun. Such ballistic uniformity is phenomenal even in comparison to the best modern guns and ammunition. As noted above, the amazing velocity for that era resulted from use of a far superior propellant, compared to anything available in the U. S. and to the 29.1-inch barrel.
When loaded with the best modern components, the 8mm easily duplicates original ballistics. With Rl-26, I was able to launch the 200-grain Nosler Competition bullet at 2740 fps from my M24/47 Mauser, 23.6-inch barrel, without exceeding modern CIP specification pressure for the 8mm Mauser.
As a hunting round, the 8mm will do anything the 30-06 will do. As noted in the discussions about other 8mm rounds, the one limitation in the U. S. is a dearth of modern, high-BC bullets with improved terminal performance, at least for now.
As noted, Mauser modified the case used in a Swiss blackpowder round for the prototype version of what became the 8mm Mauser case. I have been unable to identify which Swiss case was modified but I do have a solid reference to this fact. I expect that, eventually, a European cartridge collector will read this and let us know. When that happens, I will append this text accordingly.
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