I helped a race car buddy chop of his ballast with a sawzall, use the metal coarse blade and a lot of wd-40 for cutting fluid. As we sliced it up I could see different types of metal, slag, junk, etc all dumped in for 'ballast weight' so I wouldn't consider it a good source for casting bullets with. $2 a lb is nuts, that is literally the same price as PREMIUM certified alloy from rotometals.