The application of the changed particle X-ray excitation technique (CPXE) to the problem of determination of residues from gun firing is described. Preliminary results indicate that certain elements, including S, Ba, Fe, and Pb can be detected in statistically significant larger amounts on firing hands than on nonfiring hands with 90 to 98 percent confidence limits. Results for other elements including K, Ca, Sb, Cr, Mn, Ni, Cu, are also discussed. The simplicity of the technique, together with the number of elements detected, offers advantages over other techniques for firearm discharge residue detection.