Hi all. Just wanted to reprise a recent thread on this subject anew. As a retired CE (undergrad) and organic research chemist thereafter, the best quantitative and qualitative method to unravel a lead bullet's alloy composition is not mass spectroscopy, which requires volatilization of the sample in question. For metals, not so good. Atomic Absorption Spectroscopy (AAS) is de regur for metallic alloy analyses.

From a historical perspective in the 19th century, lead and tin was mined in Wales with, obviously, other Continental sources availability. The finer points on lead bullet alloy composition were crude. There is a lot of historically interesting forensic documentation on bronze alloys of statuary from the Greek, Roman and Renaissance period regarding whence the copper, tin, antimony and other trace metal components were sourced. I am posting a link as an example of such is presently done. Not rocket science, but such analysis is routinely used by forensic entities when required to figure out (think DEA, HLS, FBI) where munitions may have come from (think Afghanistan/Russia) in the shady realm of arms and ammunition sourcing.
Here is the link, a long pdf file from Lasalle School of Engineering, across the river from me,which is very interesting. The relevant reference to lead bullet analysis is on page 216.

http://www1.lasalle.edu/~prushan/Intrumental%20Analysis_files/AA-Perkin%20Elmer%20guide%20to%20all!.pdf

Very interesting. What is the practical recommendation for ascertaining the old bullet’s makeup? We can’t spend a fortune, can’t wait a year, etc. If you know of cheap, easy labs doing what you suggest, especially in PA, please tell me. I’ll take the bullet there. In lieu of that, Mass Spec seems the practical solution to the basic problem we are seeking to solve here. Thanks!