How many shots in a group for the ES/SD stats? I'm not sure that those are the stats to focus on at this point because you said group sizes are blown up over 1MOA. You might be better off to stop working on numbers and fix the bad group problem by running an OCW test to shrink group sizes down first, then worry what the paper numbers show. Start at 0.020" off with the bottom book load, run a 0.2gn ladder, and look at where the vertical stays tight.
I'm absolutely, 100% unrepentantly a numbers nerd and will go on for hours about nuanced BS to manage your muzzle velocity stats, but if you're over 1MOA on group size you have to solve the problem before statistics. I ran a full blown on work up on my 6.5CM - coarse seating depth test, velocity ladder, neck tension adjustments, yada yada yada, have a stack of paper data, and after all that ended up using a pretty low charge weight that runs 2750FPS on the nose, about a 1gn wide node, 0.020" off the lands, and it shoots under half an inch at 100. Didn't give a rip that is was a 5 shot SD of 8, ES of 13 because I didn't find that out until after I pulled down the target with a 0.4" group on it. I wasted a ton of components to get data instead of just looking at the target.