First of all, those are still pretty decent groups. So as far as hunting accuracy goes, I think you'll be fine just the way you are. However, I understand the desire to get the best accuracy possible. I would try some different powder charges - using 5 grain increments (i.e. 85 grains, 95, 105). Try and keep everything as consistent as possible - seating pressure, etc. Let the barrel cool down between shots. These things all should help.