The ladder test results end up being confusing for many.
I'm going to post a link to a pretty much textbook OCW test at another forum. He shot six graduations, and (for whatever reason) chose to go right to left on the bottom row, then left to right on top row. OCW was decided to be 47.2 grains, and this load has shown the continued ability to shoot into one hole--from a factory rifle. (Admittedly a very accurate factory rilfe).
And below is a sketch of how the typical OCW test should go.