Distribution and properties of gunshot residue originating from a Luger 9mm ammunition in the vicinity of the shooting gun

Abstract 

Examinations of various features of gunshot residue (GSR) collected from targets in a function of the shooting distance as well as from hands and the forearm, front and back parts of the upper clothing of the shooting person were performed with SEM-EDX. GSR samples were obtained using Walther P-99 pistol and Luger 9mm ammunition of Polish production. The experiments were designed in such a manner that the substrates for collecting GSR reminded the ones usually obtained for examinations within criminal cases. Results of the performed examinations in the form of parameters describing GSR particles: the number of GSR, proportions of their chemical classes as well as their sizes revealed a dependence on the shooting distance both, in the direction of shooting and backwards, i.e. on the shooting person. The analysis of the distribution of particles in the vicinity of the shooting gun may be utilised in description of the general rules of the dispersion of GSR as well as in the reconstruction of a real shooting case.

Keywords: Forensic science, Gunshot residue, SEM-EDX, Distribution of properties of particles in a function of the shooting range