Distribution of gunshot residue particles of a submachine gun fired at cotton fabric from the nearest vicinity – A study by means of SEM-EDX technique

Studies into shooting patterns and distribution of gunshot residue originating from a submachine gun were carried out. Multiple shootings at targets covered with cotton woven fabric using a 9 mm PM-06 submachine gun in the range of shooting distance 0 - 150 cm were performed. Optical examinations of the patterns revealed a cross-like tear of the fabric for the contact shot and for distances 1 cm and 2 cm, whereas for semi-automatic pistols of the same calibre cross-like openings were observed only for contact and 1 cm shots. Samples of inorganic residue collected from shooting patterns were examined with scanning electron microscopy and energy dispersive X-ray spectrometry (SEM-EDX) in the automatic manner. Results of the measurements provided information on the abundance, chemical composition and distribution of sizes of the populations of the revealed particles in relation to the shooting distance. The data reflected a greater dynamics of the spread and deposition of particles comparing to results of studies for particles obtained using a semiautomatic pistol of the same or similar calibres. The average values of the total numbers of GSR particles in relation to the shooting distance were detected in the range of distances between 5 cm and 50 cm, whereas, in the case of data obtained using a semiautomatic pistols rather narrow peak of numbers of particles was observed in the range of distances about 10 - 20 cm. The information on the distribution of particles originating from the use of a submachine pistol can be supportive in forensic casework.