I bought a Lee Lead hardness Testing kit to test the hardness of lead alloys I use for casting. My hardness tester at work won't go down that far. This thing works by applying 60 pounds of force to a ball that indents the lead and then you use the 20x scope that has a scale from 0-.100" in .002" increments. You measure the width of the indent in the lead and look it up on a chart that tells you the Brinell hardness. This is also the "strength of the material in PSI. So, you adjust the pressure on the lead to 10% below the strength of the lead, but high enough pressure to get some plastic deformation.
Great tool! Everybody I've shown this to wants a scope. I haven't been able to find them separate from the kit, has anybody seen any available?