Wyldeshot, Have you considered .460 Rowland? If 10mm gives 728 fpe, .460 Rowland will give you 957 fpe. And you can still back it down to 355 fpe by shooting .45 acp out of it. I think of it as magnum power on a shock absorber.
Buzz Saw, Thank you.
Really!!! I have not thought of this. You have my ears if I can shoot .45 out of it too. I don't know much about the .460 round.