Yep, too hot when they frost. I generally take it as the sign to rotate my molds when casting with the Lees. If it comes on too quickly I turn down the heat.
The pock marks, I agree, a contaminant, likely lube from the sprue hinge, seen it before, first hand :grin:
The last thing you want to do on aluminum molds is stike the aluminum block, easiest way to ruin a mold. Hit the hinge with a wooden dowel, I use an old hammer handle.
SEPAflint, if you are having trouble with boolits filling out, a smidge of tin, added to your melt, will do wonders. The right temp also makes a world of differnce.
Another thing you can do, with a bottom pour pot, is try "pressure casting". Simply hold the mold up tight to the pour spout(you'll find it fits in the sprue plate nicely) and pour 'till full. I have had mixed results with this, depends on the mold, but it may be worth a try for filling out molds as a last resort.
Finally a casting thermometer and Lyman's Cast Bullet Handbook are great investments to get good projectiles.
YMMV
