Under Water Lead Cable

[rintinglen]

Were it I, that would not be in my lead pot. I have an old cast iron pot that I use for smelting, and I would be doing about 40 pounds at a time with a big handful of sawdust followed by a candle stub of wax, stirring constantly for about five minutes. I'd flux it and scrape out the scum about three times before pouring it into ingots (may have to flux and clean it four or five times to get the crud out.) I would not waste any tin on the melt until I had it at least reasonably clean
I'd not even try a boolit until I had the melt clean.

The boolits you show are very likely cast from a really cold mold. I'd preheat the mold before casting and then I'd cast a freaking bunch before I even looked at a single boolit.

[Soundguy]

This ^

[GlocksareGood]

I have melted several hundred pounds of lead cable jackets over the years. All came from medium voltage lead cable also called PILC. It makes good bullets I just usually mix it 50/50 with COWW cause it is a little softer. I have never had any filler material in it.
I did melt down 50lbs of lead blankets from the navy yard. It was pure soft lead but had about 20% by weight of some filler. The filler came out when I melted the "lead cloth" down in a pot. I just skimmed it off the top.

[Buck Shot]

If that's cadmium coming out of your melt, be very careful with it. I know from welding that cadmium fumes will kill you in a hurry. In vapor form, I believe it's one of the most toxic metals out there.