NCJ Number
222342
Journal
Journal of Forensic Sciences Volume: 53 Issue: 2 Dated: March 2008 Pages: 321-324
Date Published
March 2008
Length
4 pages
Annotation
This study used atomic absorption spectroscopy (AAS) as a means of determining the lead (Pb) pattern around bullet holes produced by a Colt 38 Special on test targets at 5, 10, 20, 25, 30, 35, 40, 45, 50, 60, 80, and 100 cm distances.
Abstract
The study found that the lead concentration on the target, as determined by AAS, could accurately estimate short firing distances up to 100 cm. Combined with the usual macro and microscopic assessment of the bullet residues and the color reaction test (Rhodizonate test), AAS was useful in solving cases that posed greater difficulties. The study findings show a linear relationship between the firing distance and the lead amounts on well-defined areas of the target. This was especially evident when the lead densities were calculated (total amounts on the target) rather than the absolute lead amounts. The target was created with sheets of Whatman no. 1 paper on a polystyrene support. The target was subdivided into three cut out rings (one, two, and three; with external diameters of 1.4 cm, 5 cm, and 10.2 cm, respectively). Each sample was analyzed with graphite furnace AAS. Details of this process are described. 4 tables, 3 figures, and 10 references