Hotsoup,
I'd expect a 150 Premium load to run 2800 to no more than 2900 out of a 24" bbl. 2950 is doable w/good handloads. 4831 is no doubt better than 4350 for speed and would be the next used for 150s, or another powder of similar rate.
6.5 - I have had IMR 7828 beat 4831. I'm satisfied with 7828 and therefore have not tried some of the NEWER powders that MIGHT very well beat that.
7828 give an HONEST 3100+ w/130s and will do 2900 or BETTER with a 150, depending on barrel and bll lenght.
