I've been working with Imr/Hogdon 4227 for making reduces loads for a while, no matter what load I try or test. Is it me or is the use of 4227 just one of the powers that leave a trail of soot or unburnt powder down the barrel. I have got great groups that are reliable, but still the trail of unburnt powder down the bore. Crimp, not crimped, fillers in the case or not. Anyone?