Clarity of Microstamped Identifiers as a Function of Primer Hardness and Type of Firearm Action

L. Scott Chumbley, Iowa State University
J. Kreiser, Illinois State Police
T. Lizotte, Pivotal Development, LLC
O. Ohar, Pivotal Development, LLC
T. Grieve, Iowa State University
B. King, Iowa State University
David J. Eisenmann, Iowa State University

This is an article from AFTE Journal 44 (2012): 145. Posted with permission.


The transfer of microstamped identifiers to the primers of fired cartridges was examined using a stereomicroscope and scanning electron microscope (SEM). The identifiers were placed on the firing pins of three different 9mm handguns, namely, a Sig Sauer, a Taurus, and a Hi-Point. Ten different brands of ammunition were fired from each handgun, 100 rounds being fired using each brand for a total of 1000 rounds fired per handgun. The quality of the markings was evaluated using a simple observation rubric. These results were compared to Vickers hardness values obtained from the ammunition primers and are discussed in light of the types of actions of firearms used.