Happy Day! (well sort of!) I made it to the range today for another round of load testing.
This time it is Accurate #5 in .45 ACP. I made a couple minor changes. One I moved the Chrony out to 15' as suggested by Accurate Powder's ballistician, and two I changed my postion slightly so there was no bench under the muzzle of my revolver. But my arms from elbow to wrist were fully supported by the bench. The revolver was grasp with two hands, fired single action and allowed to recoil normally.
Again I was firing at a 25" wide by 65" high target carrier with a standard 50' bullseye target tacked to it as an aiming point. Accuracy results were miserable, no groups were produced. Shots scattered in a random manner from side to side and within the top 3 1/2 feet of the target carrier. I can only guess that my revolver doesn't like to be fired from the bench so I'll have to conduct accuracy testing offhand. (This might explain the poor performance I see when firing from the prone position in PPC)
Velocity results were equally as scattered. And it appears that all I proved was that manufacturers data is not to be trusted for velocities.
At the starting load my average velocity was 137 fps below published data. Roughly 15%. Likewise testing at 0.1 intervals is a waste of effort also. Velocity increases varied from 10 fps to 20 fps.
But, it appears that I'll be able to make my required 825 fps at between 8.3 and 8.5 grains of powder.