Thanks for compliment, and input.
As for my English, better part of year I spend at sea in multicultural enviroment working with Brits (scotish, english, cornish), French, Belgian, Filipinos, Russians, and with all other nationalities ashore with english language as official. (I called more then 65 different coastal states in my carier).
As I work as a Captain of large vessels, the orders down the chain of command must be clear, precise, simple and understandable. On the other side - when making my report on something, I want to make sure the persons reading it behind the desk will understand it and get my point.
Thus, the english!
Getting back to the subject.
In the mean time I received makers advice by email:
From Lee Precision:
From Pietta Costumer support:
"We do not suggest to use conical bullet but rounded bullet: .451 or .454
Your gun will work perfectly with 20-22 grains of black powder"
This gets us back to square one, I guess!
But as my inital inquiry was which conical bullet would suit the best (456 or 450), so far we came down definitely to mold 450-200 gr.