ive loaded the 340 lyman and lee .458 bullets in the 45 colt by sizing them down to .454 Did this many years ago but if i remember the lee bullet shot real well. KInd of tough on the star sizer though so if you want to do alot of it id recomend you buy maybe a 455 lee sizer and size them in it with your single stage press first then run them through your lube sizer to lube and get your final size.