Backtracking from 900, at distances are you connecting dots to finish the trajectory curve?
He didn’t mention it explicitly in that post describing his process, but part of “backtracking” is confirming actual turret adjustment increments, which can be done using a TTT (tall-target test). By removing that variable from the equation, any inconsistencies in trajectory can be traced back to either velocity or BC error (or possibly a little of both), assuming all your other inputs are correct.
