picked up some lead alloy, need identification
I picked up some bars of lead alloy a few weeks ago while cleaning out an old garage. some of the bars are marked "National Lead 666", a few are marked MF 50/50, and some Kester 30/70. I did google and found the 666 was 39% tin, 1% antimony, and 66% lead. I could not find anything about he others, I assume the 50/50 is half lead half tin? What is the 30/70? 30 tin, 70 lead?
Any help is appreciated.