In the early 1920’s, Germany’s Waffenfabrik Mauser AG, introduced the 10.75×68 Mauser cartridge. The round was chambered initially in Oberndorf Mauser Sporters and French Brevex and Rival rifles. Post WW II the round was also offered by Belgium’s Browning Arms Company and France’s Dumoulin for European customers. The 10,75×68, including comma in place of decimal point, is a currentCIP listing.
Produced with a 347 grain bullet and intended for big and dangerous game hunting in Africa & India, its low sectional density, soft pointed bullet yielded insufficient penetration for use on elephant, rhino and similar thick skinned game 1)2) and the cartridge was not as flexible in bullet weight and/or power as the 375 H&H. That said, its original ballistics are relatively decent –
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10.75×68 Factory Ballistics |
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| Yards | Muzzle | 100 | 200 | 300 | 400 | 500 |
| FPS | 2230 | 2005 | 1795 | 1605 | 1430 | 1280 |
| Ft-Lbs | 3831 | 3102 | 2248 | 1986 | 1576 | 1264 |
| Trajectory “ | – | 0 | -7 | -25 | -57 | -106 |
| Trajectory “ | – | 4 | 0 | -15 | -42 | -88 |
It is an interesting historical dismissal of a cartridge that produces the ballistics of modern high pressure 350 grain 45-70 load, a load that 45-70 fans reference when they want to demonstrate the power of the round. The thing I can’t find in research is why the 347 grain bullet standard. Why not the 400 grain standard of the similar size 404 Jeffery (AKA 10.75×73) or any number of better 0.423″ bullets? Currently, there are two dozen 0.423″ bullets with workable cannelure placement, solids and expanding from a pool of five manufacturers: Barnes, Hawk, Hornady, Swift, and Woodleigh. Available weights in grains are: 350, 347, 400, and 450.
So the bullet issue us resolved in terms of construction, but what about external ballistics? The 10.75×68 is not a whiz bang round in original form, some of it which can be attributed to pressure or, more specifically, a modest amount of the same. The 10.75×68 Mauser operates at only 47,862 psi in deference to less than consistently burn powder types, extremely hot and humid environments and rifles with less than precise chambers cartridges were loaded with a broad margin of safety. I do not think low action strength were the limiting factor regarding pressure as magnum rifle actions like the Brevex were strong enough to be used in early 378 and 460 Weatherby magnums that operate at just under 64,000 psi.
Below is the 10.75×68 at standard pressure with a Swift A-Frame 400 grain bullet, zeroed at 175 yards and with a +3″ max ordinate:
| Indices | 400 grain Swift A-Frame Point Blank Range 205 Yards |
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| Yards | 0 | 50 | 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 |
| Velocity – fps | 2080 | 1978 | 1879 | 1783 | 1690 | 1601 | 1517 | 1438 | 1364 | 1295 | 1234 |
| Energy – ft.-lbs. | 3842 | 3474 | 3134 | 2822 | 2535 | 2276 | 2044 | 1837 | 1652 | 1490 | 1352 |
| Momentum – lbs-sec | 3.68 | 3.50 | 3.33 |
3.16 | 2.99 | 2.83 | 2.69 | 2.55 | 2.41 | 2.29 | 2.18 |
| Path – in. | -1.5 | 1.9 | 3.0 | 1.7 | -2.4 | -9.5 | -20.0 | -34.3 | -52.8 | -75.9 | -104.3 |
Beyond 100 yards, the 10.75×68 Mauser well outperforms the 375 H&H with 300 grain bullet in kinetic energy and momentum. So what happens if the 10.75×68 is loaded to a higher but sane pressure and bolt thrust that could easily be handed by a Mauser action?
| Indices | 400 grain Swift A-Frame Point Blank Range 217 Yards |
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| Yards | 0 | 50 | 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 |
| Velocity – fps | 2206 | 2100 | 1997 | 1898 | 1801 | 1707 | 1618 | 1533 | 1453 | 1378 | 1308 |
| Energy – ft.-lbs. | 4322 | 3917 | 3543 | 3198 | 2880 | 2589 | 2324 | 2087 | 1875 | 1686 | 1519 |
| Momentum – lbs-sec | 3.90 | 3.72 | 3.54 | 3.36 | 3.19 | 3.02 | 2.86 | 2.71 | 2.57 | 2.44 | 2.31 |
| Path – in. | -1.5 | 1.7 | 3.0 | 2.1 | -1.3 | -7.3 | -16.3 | -28.6 | -44.6 | -64.8 | -89.5 |
With the 10.75×68 loaded to 58,000 psi, at 100 yards and beyond the 10.75×68 with a 400 grain outperform 500 grain loads for the 458 Winchester Magnum.
Dare to be different… and maybe learn something in the process
The 10.75x 68 Mauser came to mind during a search for something to serve as the subject for an interesting reloading project. Bertram brass is available from several sources at a reasonable price, bullets are readily available and even vintage Kynoch and RWS loaded ammo can be found at reasonable prices. While not inexpensive at $265, RCBS makes a full length sizer dies set #RCBS56522. CH4D also offers a die set, 10.75x68Mau for just under $200.
The big attraction to this round, at least for me, are the vintage, well seasoned and absolutely beautiful old Mausers and Mauser customs chambered for this round that are out there on used gun and auction sites at reasonable prices.
At this moment, I don’t know if we will or will not pursue this, but it seemed an interesting cartridge to take a closer look.
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