February 09, 2021
By Allan Jones
I suffer a fascination with interesting cartridges that exist just off the beaten path. Several are metric cartridges used in African colonies whose overseers were mainland Europeans, not English. I’ve found interesting ballistic considerations—and some survivors—among these pre-1940 cartridges. German, Austrian, and Dutch colonials were more likely to use magazine rifles rather than double guns, and the cartridges reflect this.
I am a ballistician, not a professional big-game hunter. I look to technical merits. In researching, I found repeated references to hunter and author John Taylor. I’d owned his book Pondoro for years but not African Rifles and Cartridges that he wrote in 1948. To eliminate middleman interpretations, I found a very affordable facsimile copy that was reissued by Martino Press in 2014. Any hunting observations here are Taylor’s, not mine.
Loaded in Europe, the 8x57mm Mauser is no weakling like U.S. 8mm offerings. European loads approach 60,000 psi, and field performance is close to that of the .30-06. RWS catalogs a 198-grain bullet at 2,540 fps, and earlier loadings included a 227-grain bullet that gave deep penetration on large, non-dangerous game.
The 8x64Smm Brenneke was essentially an 8mm-06. Factory ammo could push a 227-grain bullet over 2,550 fps with about 3,350 ft-lbs at the muzzle. Ex-military 8x57 Mauser rifles usually could be converted to handle the Brenneke’s longer COL (only slightly longer than the .30-06) with some magazine and receiver ring modifications.
The 9x57mm and 9.3x57mm cartridges were relatively easy upgrades from the 8x57mm. The 9x57mm was popular enough that it was loaded in the United States. Remington and Winchester built bolt rifles chambered for it. Factory bullets up to 286 grains offered decent penetration on non-dangerous game. Performance falls between the .358 Winchester and .35 Whelen cartridges, and it had the advantage of offering relatively straightforward conversions by rebarreling surplus Mauser 8x57mm rifles.
The 9.3x62mm remains a popular and viable cartridge. The RWS catalog for 2020 shows nine loads for it, only one less than for the .300 Winchester Magnum. The published velocity for the 9.3x62mm with a 258-grain bullet is 2,550 fps, 165 fps ahead of the .35 Whelen’s nominals. Bullet weights up to 293 grains are cataloged. Taylor speaks highly of the 9.3x62mm, claiming penetration on large game exceeds the bigger 10.75x68mm by virtue of bullets with better sectional density.
The 9.3x62mm is now listed among SAAMI standard cartridges, with a piezo maximum average pressure of 57,500 psi. Several U.S. companies load it with bullets of the latest design, and handloaders have an excellent selection of component bullets, both domestic and imported. This cartridge is trending up—a survivor, for sure.
Another survivor to the 9.3mm arena is the 9.3x64mm that Brenneke built on a 0.507-inch non-belted case head, and current CIP pressure specs are on par with the most powerful magnums. RWS catalogs two loads—with 184- and 293-grain bullets—and both are very close to .375 H&H performance.
The 10.75x68mm Mauser was a common heavy cartridge introduced in the 1920s. Its 2.67-inch non-belted case with a 0.495-inch head diameter and a tiny 28-degree shoulder held a 0.424-inch projectile. It was very close to the older .425 Westley-Richards in case length, bullet diameter, and CIP pressure standards (around 48,000 psi). However, factory ammo for the Mauser version was constrained to 347-grain bullets.
In the “Big Bruiser” department, mainland European cartridges for magazine rifles are not well represented. The survivor that is clearly of metric origin is the 12.7x70mm Schuler, and it moves 535-grain bullets to 2,400 fps. You know it better as the .500 Jeffery. Apparently, W.J. Jeffery & Co. felt an Imperial moniker was more saleable to well-heeled English veterans who’d experienced metric cartridges fired in their direction in the trenches of World War I. Taylor was highly impressed by this one, regardless of what name you call it.
I have noted some technical points in what I’ve experienced and read. First, even when lacking a pronounced shoulder for headspacing, these cartridges seldom had a belted case. The beltless magnum with a rebated rim is nothing new. Narrow shoulders can create misfires, but Taylor puts primers and environmental effects over lack of headspace control. If the shoulder hardness has a manufacturing specification, misfires can be virtually eliminated.
Second, when you look at COL, these cartridges are clearly held back for bolt rifles. Even the massive 12.7mm Schuler is held to a max COL of 88mm, only 0.12 inch over .30-06 max COL. In the case of the 10.75x68, the quest to keep COL under 81mm (3.19 inches) may be the reason for the unusually light bullet—light equals shorter.
Taylor and others have raised concerns with the construction of pre-World War II solid (FMJ) bullets for dangerous game. They thought the solids made by mainland Europe companies were inferior to the English versions Although there are certainly issues of material choices at play, Taylor’s book has cutaway illustrations detailing English solids showing thicker jacket metal at the tip than on the bearing surfaces. I’d love to hear Taylor’s views on the amazing solids we enjoy today.
With minor adjustments to reflect today’s cartridge options, I consider Taylor’s observations still pertinent to any hunter who includes research among key tools for success.