If you warm the mold by puting the bottom front cornors in melted lead or warming the bottom over the stove before you start it will help [now I did say warm that only about half the temo. of melted lead] and a small peice of bees wax syired in after the leads melted helps to; Be carful! make sure there is no moisture at all in the molds before you start to pour if there is it will turn to steam and spit melted lead all over. Lee