The embattled Boer commandos of the Boer War period did indeed make use of the 7x57mm Mauser cartridge and the then-new British .303 Enfields when captured ones became available, but the 7,65mm Mauser was the more common chambering of their rifles. It wasn't until I actually went to South Africa and was given the opportunity to handle some of the rifles so used, almost always 29-inch barrelled longrange target or infantryman's versions, and very commonly still in daily use with the grandsons and great grandsons of those who used them back then, that I noted the variety. A few thousand Japanese 6.5mm Arisaka Model 38 rifles also turned up in that theatre of war as well, it seems.
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