AFTE Store - An Empirical Study/Validation Test Pertaining to the Reproducibility of Toolmarks on 20,000 Bullets Fired Through M240 Machine Gun Barrels

This article is a follow-up to an article that was published in the AFTE Journal-Volume 44, Number 3-Summer 2012, titled Reproducibility of Toolmarks on 20,000 Bullets fired through an M240 Machine Gun Barrel [1]. Using a second M240 Machine gun with its original barrel, along with a new spare barrel assembly, thirty (30) additional bullets were test fired through both barrels and subsequently inter-compared blindly by four firearm and toolmark examiners, one of which had just completed his formal two-year training period. Additionally, the recovered (60) test fired bullets from both barrels were also mixed with the 127 bullets recovered during the test firing of 20,000 bullets in the reproducibility study and examined by the four firearm and toolmark examiners in a blind test study, in order to determine whether or not the examiners could correctly identify or eliminate the bullets as being fired through the correct barrel.

Full Journal: AFTE Journal Vol 45 No 3 (2013)