I'm trying to think of the book(s).

But I remember reading the 8x60 was popular (which is the 8x57 slightly lengthened).

The 10.75x68 was infamous. Many claiming it was inferior but probably due to the inferior 347 gr FMJ projectile which wasn't well constructed. Reference to this was in Harry Manners' book "Kambaku". Manners was a German descended ivory hunter in Mozambique. He rejected the 10.75x68 for a Winchester 70 in .375 H&H and later two of them.

The 7x57 was a popular round in South Africa as it was a Boer military and para-military round.

I remember a German hunter (not African) used a 7mm Super Express vom Hofe as his plains game and mountain round in Africa and Asia. I think his heavy rifle was a .500 NE double. Harold Wolfe of "Hatari Times" wrote about him in one of his issues. Maybe someone else can post his name.

Alf would be a great person to answer your questions especially with regard to Mausers.