From time to time I've seen posts here from skirmishers with Lee mould problems. Here are a couple links to Cast Boolits Group articles, stolen straight from a posting at muzzleloadingforum.com, that appear to offer some answers:

http://ktsammo.250x.com/castboolits/cst2.html

and

http://ktsammo.250x.com/castboolits/cst5.html

Happy New Year, everyone!!