I can't help you on the Norma,great choice in calibers,but I have just started loading the 264,my research suggests powders in the slow to very slow.4831 class(RL22,N-160,N-560)for the 125 or 129 bullets. The standard big game load is the 140,in this you slow down,H870,AA8700,RL25,H1000 or...