Hallo Paatti,

a cupple of years ago, i´ve saw on the local shootingrange here an owner of a old drilling in 16gage and 11,15x65R (blackpowder). In a old german catalouge from 1911 this calibre belongs to the standart.
Last year somebody sells a drilling (not a Sauer&Sohn) in 12gage and 10,75x52R.
This bouth and the 11,15x60R/M71 (.43Mauser) were the most uesed 11mm-rimed-calibres between 1870 and 1920.
After World-war I, this calibre were completly gone. Arrond the late 1880´s the caliber like 8x57R/360, 9,3x72R, 9,3x82R were more used. First with blackpowder and lead-buillets, later with smokeless powder and nickel-coatet buillets.
The 11,2x72R could be the rimed version of the 11,2x72 Schüler, a german big-game-cartrige of 1904, which is from the power not very far from the new .450Rigby Mag.
The rimed version of this cartrige an d the rimed 10,75x57 were also in the old gun-catalouge from 1911, but they are very rare, maybe there were just a few guns build for them.

regards from Germany
Manolito