Defcon-one, I am one of "those guys" who asked all those "rude" questions.
I still stand by my comments. Wheel weights are obviously quite variable in their makeup. If you want precise alloys but the, from a foundry. Use of scrap for an alloy negates any ability to know precisely what the composition is. Well used Linotype isn't the same as fou dry new Linotype, is it?
In the end, most of us just don't worry over this stuff. I find a mix that works for me so I use it. Wo cares what the exact composition is, it works!
Wheel weights of today vary from manufacturer to manufacturer. Throw in weights from different eras and who knows what exactly you have. To my way of thinking of I know a ballpark figure it allows me to make up a mix of scrap that will get me the properties I want.
If I want to know preciscely what is in my lead I will need to find a place that can test it for me. I don't know of any, haven't really looked.
This isn't meant as any form of an attack. It is only my opinion. The info from Goodsteel only shows that wheel weights are not a very homogenous source of alloy. What you get can vary from batch to batch. In the end, does it matter in the gun or on the target? That is what counts to me.
Use what you want, test what you want, just don't get so wrapped up in details that you lose sight of the big picture. Most guns will never, ever know the difference.
I like to keep things simple. I cast, I load, I shoot. I dont fret over small details about alloy as it isn't very fun to me. I try to keep my shooting fun.