Such old custom loaded 9.3x72R cartridges were likely loaded post WW2 when ammo in most metric calibers was not available except for very hard to find limited stocks of pre or wartime production. Cases for long, near 30-30 head size cartridges such as 9.3x72R and 8x72R were not available and custom handloaders had to resort to re-drawing American cases to the necessary length and smaller diameter head size. The 30-06 and 30-40 Krag were used to make such cases. I have a couple 8x72R cases in my accumulation of cases, that were re-drawn from 30-06 and remember seeing old adverts. for such cases made from 30-40 Krag. The situation became less and less dire until now even boxer primed 9.3x72R are not too hard to find.
Mike
Interestingly, my old box is labeled Remington 30-40 Krag unprimed Cases.
