You are making me do math , my Chrono does all that ES & SD for me , well, both of mine do !
The reason I asked was , that the best ( lowest ) SD is alway what I go for , but it does boil down to best group . The best SD seems to be the most consistent in grouping for all those I test , but not always.
Don't completely rely on the Primers for high Pressure signs , the fired Case can show HP signs earlier then the Primer .
Looks like your loads are shooting pretty good , which do you like ? I like # 4 or # 8