Thanks for the great info...

The gun is a guild gun prob. pre-war I imagine...It is gorgeous sidelock w/ 2 sets of barrles and nice engraving ect...One barrel is 16 x2 the other is 16 x what they say is 11mm??

I have talked to them and they have said they could chamber cast it for me...If it turned out to be a decent readily avail catridge it may be worth my while...But if it is very rare or I have to re-load myself, or is not a very powerful catridge I would pass....I don't need the hassles at this time..I assumed it was a 8x57 or 9x72....I was hoping for something more powerful...With chamber casting think they will be able to narrrow it down or should I be careful they may tell me something I want to hear as to sell it??