I'd almost consider running the ladder again for the sake of clarity but clearly there is a node at around 43.2 grains. Also I want this barrel to last at least one year so I'm going to do a little more testing for seating depth and SD and call it good. Also I'm not a benchrest shooter, I'm a steel shooter. I just want a reasonably accurate load that'l be consistent year around.
But still I'll take a 5 shot .9" group at 400Y """(OH YEAH)""" with a half grain difference in charge weight, "including excuses" any day, LOL.
When a person does a ladder it is assumed that there is going to be some kind of wind, thus the horizontal is not critical as we are looking at where the vertical stops. Although yes if the wind condition remains constant the Horizontal will tighten when the node is hit.