Unclenick - thanks for the lead for the On Target software.
I’ve been testing pistol ammo shooting off a rest with targets set at 50 feet. I generally use plain white paper, either 11x17 or 13x18. I find it easier to have a small point of aim of around 1" diameter when I'm shooting open sights, so I mostly use little adhesive target dots. The aim point is 6:00, the bottom of the dot. I'll put two dots on each sheet of paper, so I don't need to change targets as often.
Make sure you label the targets!
I use 7 to 10 rounds per specific configuration of components, but if you are going to load 15 rounds you may want to consider testing as follows:
1. Shoot ten rounds or more before starting testing. I find it helps me to get in the “groove” before starting testing. Even after years of shooting, I still get a rush when I first start pulling the trigger. Maybe, it’s just me.
2. Starting a lowest powder charge, shoot 8 rounds, checking for pressure signs, pistol operation, etc. Label target and replace with new target.
3. Shoot 8 rounds from the next lowest powder charge, checking everything, change targets and continue this process through your whole series.
4. You should have 7 rounds of each specific powder charge left.
5. Place a fresh target and shoot the 7 rounds of your highest powder charge. Work your way back down to the bottom.
Following this method will give you two targets for each load. I find that I get fatigued after shooting for a while (hauling my big bohunkus down range and back, bearing down on pistol grip, etc.), so this method of proceeding up, then back down through the specific charges helps me to balance out the effects of fatigue.
Let us know your results.
A lack of planning on your part does not necessarily constitute an emergency on my part.