"Stronger than the original? Please enlighten me. Since the schnellfuerer models were machine pistols, and the original chambering was in 7.62x25, i.e., .30 Mauser, I'm not following you here."
Schnellenfuerers (Mauser 712, as I recall) were full auto, but the original C-96 'Broomhandle' Mauser was a semi-auto. The 712 and a few other C-96 models had detchable magazines - but most were fed via stripper clips.
Newer metallurgy allows for stronger metals. The Mauser could take a 9mm after having the bore drilled out - with turn-of-the-century metals. New, stronger stuff could handle higher pressures and more powerful ammo than before. It could easily handle .45 or 10mm.
The .30 Mauser/7.63 Mauser is practically identical to 7.62x25 Tokarev (which is very cheap, this ammo was made for the Tokarev pistol and the CZ-52).