I hesitate to bring this up because to most will probably think that I am coming from left field, and I understand that. But I seem to remember reading somewhere recently where someone explained the whole process and I felt relieved that my experience wasn't for not.
I recently shot F Class, Mid and Long Range competition (600 yards and 1000 yards) and attained an expert classification in long range and master classification in mid range. That is only about mid level of the competition but does demand accurate hand loads. I learned a great deal doing it and want to bring certain techniques out in the open for discussion.
Berger Bullets were the most popular bullet for the class and their technicians were readily available by telephone for coaching. To find the most accurate load for a new rifle/bullet often began with finding the "jump" of the bullet before hitting the lands. I would load 5 with .010 jump, 5 with .015, 5 with .020, etc and test them at 100 yards. It was surprisingly clear which jump the rifle liked the best, and we found that the patterns would repeat themselves every .040 or so.
Once we found the jump it liked we would move on to the powder charge to give the velocity that we were looking for, and testing was also done across a chronograph to find the sweet spot, where velocities and POI elevation between a few different powder charges stayed the same or at least close. Having done this on several rifles/barrels recently I can't help thinking the same process would work with pistols (pistol caliber carbines) even though there are other factors to be considered, like magazine length and feeding.
I may be forgetting something pertinent right now but I want to put this out here for feedback. Thanks in advance.
Richard