I would try the Alliant line up of R16, R23, & R26 depending on bullet weight. These have done well in the 25-06, 270, & 280 AI so should be good in the 6.5-06. I would bet that R23 will work for the full range of bullets so would probably start there. R26 will give the fastest speeds especially with the heavier bullets so would be first choice for 130+ grain bullets.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli