I have a Redfield Revolution 3-9x40 accu range on my old beat up 77,and love it .It would be good for your application I think ..I think that either IMR,or H 4350 is good all around powder for the long action stuff,and it's always easy to find...I just got a good deal on a model six in 270 a few days back,and it has a Redfield widefield 3-9 on it.It has see thru mounts which I aint a fan of,but I don't think I would mind them on a 06 loaded as heavy as you intend especially if they were already there.
