Remember that the chamber is only part of the equation. The barrel and its harmonics are just as important. ES/SD are a product of chamber size, barrel internal size, rifiling, smoothness, twist, and harmonics. Even if they are the same length and made one after the other. Sometimes you get lucky and they are really close but all mine are a story to themselves. I find handgun barrels are often closer in performance and feel it is due to being shorter and having less influence on the bullet as it travels through it. But that is a personal observation. There are some caliber bullet size/weight combos that are really accurate in many different firearms but that does not hold true for the majority. I will often "cheat" and try an established load in a new gun and try tweaking from there. My usual tuning method is to do a full workup find the widest accuracy node (usually the lowest) and test in the center of that trying different bullet insertion lengths/crimp or not etc. to maximize accuracy. Low ES/SD often is in the center of that accuracy node as well. I guess it depends on how accurate you need each gun to be as to the extreme you go to.