My thoughts Dac was a 60lb. bag of concrete would yield two weights using Kenny's design at 30 plus pounds once you add the metal. Using concrete would be a good substitute if you don't have any lead.I didn't mean that concrete was heavier, obviously it's not. Jim mentioned concrete and I thought these would at least add considerable weight. I still need to find my scale to satisfy my curiosity though! Finding lead cheap or free can be pretty tough.
DAC