Buy a thermometer for your casting pot. Don't guess. Those numbers on the dial are only guesses. Most pure lead is cast at about 700 degrees F. It melts at about 650 degrees F. With lee molds, you need to leave the mold block resting on the top edge of the pot to heat it sufficiently before pouring lead into it, to avoid rinkles, and air pockets. You want the pour hole as close to your spout as possible when you pour, so the lead is NOT traveling through much air before it reaches the mold. If you are using a ladle to transfer lead from the pot to the mold, remember that the ladle also has to be kept very hot so that the lead does not cool down before entering the mold. I lay my ladle right on the molten lead, or put it in it. When its hot enough, he lead will flow off the metal parts like water off a duck's back. I put the mold as close to the edge of the pot as I can, then lift the ladle out of the lead, and pour the molten lead into the mold over the pot. Any spills or drips go back into the pot. If I can, I actually put the bottom of the mold block on the top edge of the pot, so that heat from convection is heating my mold up as it is about to receive molten lead.