Go to Harbor freight and get their mini chopsaw about $40, then make you a small jig that will fit in it's vice, make it out of metal or wood, metal hold up longer, drill a hole the size of the 45 case and then cut the jig to the length that you want the case to be, 45acp length. Off set the hole some but you will have to rotate the brass some to cut all the way through, then just de-bur the brass