Well if you are using your clicks. I would say the same as holly try a highter mag. I would go as big as you can befor the center moves to much. I have a 8-32 mag scope and i just leave it on 32.
I have used a big nikko 10-50 mag and i liked it on 50 to range find then 40 to shoot.
Its up to you but i would say as big as you can.