I' d highly recommend using some light loads for centering your sights. For both financial and physical reasons, heavy loads aren' t the way to go. You just need to see where your gun is throwing the lead, so any load will work. Once you get your sights pretty well centered, then switch to your hunting loads to zero your sights with the center of the pattern for your load. I' d start at 15 yards with some 2 3/4" #6 loads, then move back 5 yards. Once you get your sights centered at 30yds, you should be ready to switch to hunting loads and start again from 20yds, making minor adjustments. Good luck.