How do I figure out what lead I have?

[Gus McCrae]

I have some lead roof vents and a block of lead (about 20 lbs) that is square at the bottom and a smaller sized square at the top... from the side it looks like a isosceles trapezoid.

Anyways, how do I figure out what I need to add to make a hard cast bullet for .357, .45 Colt, and .45-70?

I guess my real question is, how do I know what I'm starting with?

[David2011]

Hi Gus,

Welcome to the forum!

The roof vents are for all practical purposes pure lead. The block is going to be harder to identify but if it's from the same source it may be pure as well. A fingernail will scratch pure lead. Impacts on a block of straight lead will make a thud. The harder it is the more it will ring instead of thud. There's a sticky at the entrance to this section site that describes using drawing pencils of various hardnesses to test lead hardness. http://www.castboolits.gunloads.com/showthread.php?t=75455

Your .45 Colt doesn't need particularly hard lead as velocities should be around 850 fps. The most important characteristic is going to be the fit of the boolit to the bore more than the hardness. The general philosophy is that more speed requires more hardness but if you shoot a very hard, undersized boolit in your .357 it's going to lead the bore. Same for the .45 Colt even though it's going much slower. A softer boolit that's .001- .003 over the bore diameter will give good results for both leading and accuracy. The original .45-70 projectiles were also pretty soft, being a black powder cartridge when it was developed.

A 50/50 mix of clip-on wheel weights (COWW) and straight lead would yield an alloy suitable for .45 Colt, .45-70 and .38 Special velocities. For .357 magnum velocities you would probably want to consider gas checked boolits and possibly a little harder alloy. I think the general opinion of the old time casters here is that hardness gets overdone.

There is a enormous amount of information on this subject on the forum. There's also Glen Fryxell's information on the LASC page- http://www.lasc.us/CastBulletNotes.htm.

David

[Gus McCrae]

Thanks for the post. It cleared many things up for me.