I haven't had it happen to me but it happens. Is it a new die ? If so you need to take it apart and clean it really well then look if there are any tool marks in the seater. You may want to ask this question over at longrangehunting . There are some unbelievably experienced loaders over there . What brand of die is it ?
Thanks Guy's! ! It was a new RCBS die and the AB's were the first on the list. After two trys and two stuck bullete it started to work fine. I guess I finally got it clean enough ect...