I regulary run all my pellets and slugs through a push through type pellet sizer purchased from England via ebay. There has been a couple of times where it was more difficult to move the slug or pellet through the die without some additional help. I purchased a small machinist double headed hammer with one side a hard and dense plastic type material and a brass head on the opposite site. With a light tap on the push rod all pellets and slugs have gone through the die with no issues. Cleaning and lightly oiling the die from time to time will help with pushing things through the die.