I have seen that but only when using dirty lead, aka alloys. I rarely get pure lead from my local scrap yard so my weights are never what the mold says. 1/2 ounce jig heads were only 3/8
When I started pouring jig heads and sinkers, I didn't know the weights on molds were not right. I have a sinker mold that has a 10 oz. bank sinker which only weights 8.25 oz. Tried others and found the some thing.
The best thing my dad ever gave me was his love of fishing.
I have seen that but only when using dirty lead, aka alloys. I rarely get pure lead from my local scrap yard so my weights are never what the mold says. 1/2 ounce jig heads were only 3/8
Could have a hollow spot inside the sinker itself. A friend of mine sent me some big sinkers that he had found around rocks at a beach. I dropped one into my pot to melt down and it exploded sending lead everywhere burning my hands, had lead hanging from my eye lashes. God took care of me that day in 2011, COULD HAVE BEEN BLINDED. I posted pics here back then, maybe in the archives here. ALWAYS wear eye protection now. That sinker had a big hollow spot in center. Don't know what caused it to explode like that. Air, water ?
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