NCJ Number
218767
Date Published
July 2002
Length
8 pages
Annotation
This article offers a brief review of the basis for comparative bullet lead analysis.
Abstract
Developed in the early 1960s, comparative bullet lead analysis is possible because leads for bullets poured from separate molten batches are distinguishable. As a result, laboratory technicians can differentiate among bullets made of different alloys or can exclude a single source for bullets of the same alloy. Comparisons of the composition of bullet lead are enabled because each melt of lead has its own characteristic composition. Moreover, variability in the final bullet product can be impacted by the final step: the packaging of cartridges into boxes. Since the 1970s, most laboratory techniques for analyzing bullet lead involve the use of inductively coupled plasma-optical spectroscopy (ICP-OES), which has been widely accepted as the method of choice for most inorganic analyses. The main disadvantage of ICP-OES is that it is a destructive process that requires acid digestion. The bullet lead-manufacturing process is described, which generally uses secondary lead smelters containing raw materials primarily recycled from automobile batteries. The smelters separate the batteries into plastic, acid, and lead components. There are few physical requirements for the lead except that it must be able to be processed. Variations in lead composition resulting from the manufacturing process are reviewed and the significance of bullet lead data is considered. Figures, references