I am casting bullets from a mould that I have had good results with before. It is 214 gr and has a long tapered nose. Taper is from .3015 to .3113. I have previously cast boolits from this mould with lino. It works well. I am now casting with straight WW. On one side about 90 deg from the mould seam I get from time to time a frosty spot which does not fill out all the way. The taper is a straight line the no fill is a sag in the straight line. My temp is 650, checked with a thermometer. Has anyone had this problem before? All advice greatly appreciated.
Jeffrey