Re: God groups but bad ES
I think I would take whats behind door #1.
I would NOT be looking to change powders or primers at this point. When you are getting 1/4 MOA at 750 yards, you likely have no where to go but down. Dont try and improve it, dont try and change your ES. What ever you are doing, keep doing it.
I know everybody here says your chrony is broken or it lies or whatever. Granted they are not perfect but I can consistently read single digit ES for one rifle while getting 30+ for another at the same sessions and day after day so I know it is NOT my chrony. Yet even my 30+ ES loads shoot very well out to 600-800 yards. Mathematically and in theory the vertical should be all over the place but sometimes it just is not the case. This is due to having a good barrel/load harmonic relationship. This IMHO is 100 times more valuable that a small ES.
DONT WORRY ABOUT IT!!!!!!!
Long range shooting is a process that ends with a result. Once you start to focus on the result (where the shot goes, how big the group is, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.