One source for free lead was where I used to work. Electrical generation plant . Turbines have to be maintained and inspected on a regular basis. There is a lead seal that is removed. I forget how often they are replaced but just one would keep you in lead for a long time. It is 100% pure lead also.
It is used as a safety seal and has to melt at a certain temperature. The turbines where I worked were old 115 megawatt , small by todays standards. I can only imagine how much lead is in one of the bigger ones.
I was assigned to maint. dept during one of these outages and seen 5 gallon buckets of lead. Upon inquiry about it I was told to take as much of it as I wanted. Cheaper than having someone haul it away. As I muzzleloaded and cast jigs and sinkers at the time I took all I would ever need.
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