Don't forget about seating depth adjustment too!! I start by finding what the max velocity I can get with a powder and keep acceptable pressures... then adjust the seating depth .003" -.005" and shoot 5 shot groups at 200yds untill the groups are acceptable.
I guess I'd load up 15 of the 53 grain load, then shoot 5 @ right off the lands, 5 @ .003" off the lands and 5 @ .005-.0075 off the lands. See if that makes a difference. I've always had better luck "tuning" loads by adjusting seating depth than by tailoring powder charges... maybe it's psycho-symatic... but it works for me. ~JT