I'd go with the more common 40 degree Ackley version. Cheaper dies, all the benefits of the improved chamber. Otherwise, I'd just run a plain .25-06 and avoid the hassle.
This right here. Ditto. +1. Etc.
My most current (might be one back) Sierra manual has quite a bit of data for the .25-'06 AI FWIW, so you won't be entirely without data for pretty current powders.
Tom