I have a new Pedersoli Kentucky flintlock pistol. The trigger pull is very heavy (usually off the scale of my Lyman electronic gauge). I decided I would start with stoning the sear nose and tumbler notch. I followed Bob McBride's instructions on how to disassemble the lock (), but I can't separate the cock from the tumbler. I've put the lock across an open vise, as Bob showed, and whacked the tumbler square shank using both a brass and steel punch. I put Kroil on it and let it sit overnight and then hit it hard enough to bend the lock plate slightly, but the shank doesn't budge. I've considered heating the cock with a butane torch, but I'm concerned that that will damage the case coloring. I suppose some kind of a press is the right tool for the job, but I don't have one. Any suggestions?