Casting along, using wheel weights we smelted earlier today. Nice clean ingots put into RCBS bottom-pour casting furnace. Molten lead running well, casting good bullets, when suddenly the lead starts to run slowly, then drip, then almost stop. Furnace set at 725° F. Tried lower and higher settings to no avail.
Wot the heck went wrong??? I now have a casting furnace half full of lead that won't run out the bottom.