I shoot several 3-round groups, going up in 0.2 grain intervals, starting with one that give pMax of 56,000 psi, up to maximum pressure predicted by Quickload.
Before I hear a lot if sucking of breath and “ tut, tut you can’t trust Quickload,” let me confirm that I have successfully tweeted the parameters of all the powders I’ve used, for barrel twists from 1:8 to 1:12 based on observations and measurements over a lot of rounds shot, and I mean a lot.
Using my calculations and Optimum Barrel Times I can generally get to a node quite quickly and I’ve found, again through experience, that 56,000 psi is a known good starting point.
Just by way of experiment I tried ladder testing but the POIs are too close at 200 yards to give good results (200 yds is my home range max distance).