You could probably make good use of the ladder method.
Load one cartridge with each powder charge from minimum to maximum load going in 1/4 gr. increments. fire them at the same aiming point at 200 yards and make a note as to where each shot hits. You will likely end up with a shring of shots on the paper with one or more clusters. Pick the tightest cluster, and use the load that that is the median load in the cluster. That load in theory will give you the most robustly accurate load out of the group.

I would do a further search on "ladder load development" to give a better explaination than I did.