Find maximum charge at maximum length then play with seating. Easy to bump the bullet back. But frequently the load will shoot right off the bat.
I have heard of others doing it the opposite way but that seems backwards. I have also heard that ideal length will work for a range of varying charge weights, but this hasn't worked for me.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli