Congratulations Scott.
I should be receiving a 24' SS .250 AI from Bullberry any day now. It has a 1:10 twist. Research shows it should be a great round.
I have the Sierra manual which has nice .250 AI data. I plan on initially trying the Sierra 90 gr HPBT (supposed to be hammer on deer) and the 100 gr prohunter (another great bullet).
I too just bought the redding 2 die set, also have the lee collet to use (lee says collet will work on improved also). What are your plans to fireform? I'm planning on using 75 gr hornady HP's with a light load of H4895 from the 250 data.
Mirage