What I do:
Get you a good chrono.
Look for a powder that gives you the velocity you want at 90%+ fill, but not compressed (or not much).
Load a couple each at SAAMI length, starting at the midpoint charge and working up to the max.
Check velocity, looking for pressure signs, especially ejector marks.
Find pressure sign charge weight, then back off .5 grain.
Then I use this method:
https://bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/It has worked well for me.
P
