Nice looking setup!
At what distance were you getting those groups? I looked through the the posts and noticed that you didn't mention this.
At 25 yards:
Federal Gold Match 69 gr = dime size group.
Black Hills 75 gr Moly = quarter size group
Federal American Eagle 55 gr = quarter size group
Winchester 55 gr = 2"+ group.
At 100 yards:
Federal Gold Match 69 gr = quarter size group.
Black Hills 75 gr Moly = 2.5" group
Federal American Eagle 55 gr = 3 -4" group
Winchester 55gr = 4"+ group.
Not enough data yet, just one session. I will go out again this weekend with more precise measuring tools than pocket change.