The 1910 catalog from Burgsmüller lists as the most common calibers:
9.3x72R
9.3x82R
11x65R Drilling-Patrone (slightly conical case)

There are 11.15 mm bullets offered for reloading:
a flat nose, 47 bullets per kg (328 grains)
a round nose, 48 bullets per kg (321 grains)

It seems that a distinction between 11 mm and 11.15 mm was not made.

I have inherited some original pre-WWII 11.15 swaged lead bullets and some more bullets cast by my father from an original mold, both types weighing around 300 grains.

Fuhrmann