Firing distance estimation based on the analysis of GSR distribution on the target surface using ICP-MS-An experimental study with a 7.65 mm × 17 mm Browning pistol (.32 ACP)

Best results were obtained with samples collected at radial distances within 2.0-3.0 cm from the bullet entrance hole. Using this approach, it was possible to accurately (±6 cm) estimate the firing distance in the interval [20-90] cm from the target.