I am hoping you guys can sort me out.
I am using a 4 cavity HP mold from NOE. .453 cal 200 grain.
The last time I used it mold, it was great, put out a pile of bullets and all was right with the world.
Yesterday, I pulled it out and after preheating it, focusing on the pins and everything, the bullets welded themselves to the pins. I had to melt them off with a torch.
After more preheating, more melting bullets off with the torch, I finally got to the point where it was casting. Not fast, not smooth, but I did make some boolits. Lots of slow downs though.
I added a few more ingots, waited till temp was back up, preheated the mold a bit more with the torch and all of a sudden the sprue was so hard to cut, I broke my mallet. Nothing I could do could get that mold to cast good again.
So, I shut it down an pulled out a 2 cavity 9mm HP mold from NOE. Casted fine, bullets practically flew out of the cavities.
Alloy was at about 625 degrees according to thermometer. Around 700 degrees, the sprue was taking forever to cool. Was my alloy too hot to come off the pins or get cut by the sprue plate? Should I cool it down under 625? I plan on polishing the pins with some sand paper and steel wool today...
Help?