Differentiation of high velocity ammunition type from Gunshot Residue (GSR) metal element originating from different firearm

Abstract

The examination of GSR collected from the scene of occurrence is critical to the forensic science community because it provides answers to problems such as distinguishing between entry and exit wounds, estimating the range of fire, and linking an individual to the use of a firearm. Insufficient information exists on the differentiation of ammunition type through the analysis of GSR. This study investigated the potential of differentiating between ammunition types through the analysis of its metallic residue using Energy Dispersive X-Ray Fluorescence spectroscopy (EDXRF) and Scanning Electron Microscope Energy Dispersive X-Ray Fluorescence spectroscopy (SEM-EDS). Three firearms (AK-47 assault rifle, Self-loading rifle, and Carbine rifle) were adopted for the study. Overall, a series of 10 shots were performed from each firearm at three different collection mode (45°, 90° & Barrel wash) The residues were subjected to a non-destructive analysis by energy dispersive X-Ray fluorescence (EDXRF-7000, Shimadzu) without sample preparation and Scanning Electron Microscope Energy Dispersive X-Ray Fluorescence spectroscopy. Gunshot residues originating from 9mm Carbine, AK-47 and Self-loading rifle produced common metal element including Lead (Pb), Copper (Cu), Mercury (Hg), Antimony (Sb) and Zinc (Zn). Considering that, analysis of the sample residue was carried out EDXRF and SEM-EDS; it was unreliable to predict the ammunition type from the particles that originated from the firearm-ammunition employed. In this study element profile of Gunshot residue give some identical point which can helpful in identification of ammunition.