I've been collecting lead for years. Whenever I saw some at a garage sale I'd buy it. When diving friends got rid of their old lead weights for the fancy bags of shot I gladly took their old lead. I piled it all on our old bathroom scale. It weighed in at more than 100 pounds. Just what I needed for Ravn's ballast keel.
I had a few large pieces that I chopped up using a sledge and a steel wedge used for splitting wood. I got my little charcoal BBQ and decided to sacrifice my smallest cast iron frying pan and I was ready to melt lead.
I spent a couple hours building a wooden form. I had the foresight to put four 3/8-inch wooden dowels and some wooden disks where the holes for the bolts to secure it to the wood keel would go. Drilling wood is a lot easier and less messy than drilling lead. I then buried the form in the back yard so the sides wouldn't break out from the weight of the lead. My neighbor, Ray, and I got out the lawn chairs for an hour, maybe two, of fun. The hour stretched into more than four. Melting lead on a BBQ is possible, but I don't recommend it. My back was sore for three days afterward.
We had to melt the lead in five- to seven-pound batches. A week or so later when Ray and I carried it back into the shop the lead was stratified with voids that I filled with epoxy. I had hoped each pour would melt the last, but it didn't completely. In all, though, it looked pretty good.