I load target/practice handgun rounds to achieve off-hand shootability balanced against accuracy, and for most I start with published starting charges + maybe 10- 15% and build 10-16 rounds. Specifically, enough for 2 revolver cylinders or one semi-auto mag.
From there I add .2 - .4 grains depending on the size of the charge. For Bullseye or other fast powders, .2 is enough to discern a difference. For a 2400 load .4 is the threshold. SOme shooter might be able to distinguish a .1gr difference, but I cannot.
I build 3 levels and stop until I get a chance to fire them. That's usually enough to achieve the desired accuracy and still have an easy-shooting round. If I'm striving for critter stopping magnum rounds, it takes more levels to get there.
For rifles I go to .5gr increments and load 6-8 rounds.
