I understand. So far 4759 seems to be the only powder that will make 2,500fps in the big "8". This is unfortunate, as that is only in the ballistic range you've accomplished in the 12 bore. I would have thought this ctg. would make 2,500fps with a 1,500gr. slug. A little much for deer, but a great comfort with a charging brown bear. The shot would knock you out of the way, and quite likely stop a charge even if not a lethal hit.