In my experiences with my 06 and Varget (i shoot 180s) mine liked the middle 45.5 charge.. In everything i use Varget for it has always ended up with middle to bottom charge weights...
Best thing is start at the bottom and build 5.. Then go up .5gr and build 5.. Continue going up .5gr and making 5 til you reach max.. Then shoot different targets with each 5 round group... You will find 1 really tight group... If it 1 holes (like i did with the 45.5 charge) stick there if not go up and down .1gr twice -.1, -.2 and +.1, +.2.... From there if you want to go farther you can play with the seating depth if you want to get really really tight... But since my belief if this is a hunting gun i would be happy with either a 1/2" group at 100 or touching or something close...