All my ladle casting is done with a Rowell #2.............more than enough lead for the largest moulds. I prefer no larger than a five cavity. The mould will fit diameter, wise, inside the top of the pot. This way, excess poured alloy makes it back into the pot. IME, one can never pour too much alloy. Keeps the mould and sprew plate up to proper casting temperature. When the mould is operating correctly.............a glove hand is all that necessary to cut the sprew.
Winelover