Richard,
Apparently you chose to ignore the other part of what I plainly stated about the loads in my rifle, about figuring what velocity should be safely possible from the pressure-tested results from other cartridges around the .257 AI in size.
I don't base ANY of my handloads merely on "all the usual pressure signs." If specific, trusted data isn't available, I also look at similar rounds and use proven formulas to calculate what velocity should be safe. I have used this method for years, and when the .300 WSM first appeared, used it to produce the first published loading data. When pressure-tested data came out within the next year, my loads (based on comparison with .300 Winchester Magnum data) were all within a grain, and the vast majority were dead on or within a half grain. That is not the way things work when somebody depends TOTALLY on all the usual signs.
