Dear Andreas (450 366),
We are neighbours. You are in Sweden. I am in Latvia.
Sorry but I never wrote about “10.75x65r LK”. Such cartridge is unknown for me. May be the small mistake took place. I have mentioned 11.15x65R LK as Lancaster. Also sometimes called as Express or Lancaster Express or Shtutzen in German literature.

About comparing the base and the rimm diameters on the casting. The base diameter of camber is a little bigger now, than it was at the beginning. It is the work of my hands and my mistake. Long ago I tried to modify the chamber, but the reamer was too blunt and I stopped the action. Only the part about 12 mm length was a little increased in diameter. In my previous post I have use the correct dimention, but not the increased.

Also before that operation it was possible to put 10.75x68 Mauser in my chamber.