I have a lee 6 cav 230 gr RN mold that I have only used three times in casting. I treat it well, open the sprue plate with a gloved hand and I dont bang on it with anything. Bullets drop fine but this last time the mold was having trouble closing all the way and also opening after sprue cutting. Further investigation revealed that it was sticking on the nose pin (at the end) with the near pin coming free easily. When I finally stopped pouring (it was sticking so bad) the pin was so stuck that I almost had to pry the two mold halves apart. I didnt want to marr the mold so I was able to free the pin by wiggling and tapping with a dowell, I also checked the pin and seat, both shiny (no burs). What could be going on and what are my possible solutions?
Mike