Its been found that reducing charges of slow burning powders can lead to wild pressure swings, sometimes resulting in burst actions even w/modern magnums. (Treat this round as a mini-mag throwing crazy heavy bullets for it size.) On the other end, I suspect that the long bearing surface and high engraving forces required due to the deep rifling can create high pressures. Hornady put forth a lot of effort to make this round work as intended, so I'll defer to their expertice! Plenty of other good stuff in the new manual; its well worthwhile.