I ordered a 575-500 Lee mold and started casting today with some roof flashing scrap that thumbnail tests soft. Also, I got my new Lee Pro lead melter yesterday so I used that to melt. I have always used a cast iron pot and ladle up to now. This was eye opening. Results are of a hundred bullets about a dozen have a void in the skirt. Strangely the bullet in the photo depicting the void weighed 33.8 grams while the smooth bullet weighed 33.5 grams (521 grains @) Both measure .577 straight from the mold. Neither bullet was wrinkled as if from a cold pour. I don’t think I’ll reject the void bullets but any ideas on avoiding that result are appreciated. Lead pot tips are apropos as well.