U.S. flag

An official website of the United States government, Department of Justice.

NCJRS Virtual Library

The Virtual Library houses over 235,000 criminal justice resources, including all known OJP works.
Click here to search the NCJRS Virtual Library

Long Range Deposition of Gunshot Residue and the Mechanism of Its Transportation

NCJ Number
236829
Journal
Canadian Society of Forensic Science Journal Volume: 44 Issue: 3 Dated: September 2011 Pages: 97-104
Author(s)
Robert V. Gerard; Michael J. McVicar; Elspeth Lindsay; E. Dale Randall; Erin Harvey
Date Published
September 2011
Length
8 pages
Annotation
This study investigated forms of gunshot residue distribution: the spatial distribution in a horizontal plane, and the distribution of the residue around the point of impact on a down range target.
Abstract
Tests were performed in an indoor firing range to establish the distance gunshot residue can travel following the discharge of a firearm. Sample collection devices were positioned at the firearm's ejection port and horizontally positioned down range up to a distance of 18 m. The collection devices were analyzed for gunshot residue (GSR) using scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX). The area of highest GSR particle deposition was observed to be 13.5 m downrange of the firearm, however small numbers of particles were also found at a distance of 18 m. A target cube at a distance of 18 m was used to separate GSR particles travelling on the bullet from those travelling diffusely in the broad plume of gases emitted from the firearm. It was found that GSR particles travel in close association with the projectile as it was observed that the concentration of GSR particles on the rear target was an order of magnitude higher than the concentration on the forward target. GSR particle numbers cannot be used to distinguish between a shooter, an individual near the path of the projectile, or a shooting victim. (Published Abstract)