Individuality testing of new Glock pistol barrels "Marksman Barrel"

Stephan Christen; Hans Rudolf Jordi

doi:10.1016/j.forsciint.2018.11.028

Individuality testing of new Glock pistol barrels "Marksman Barrel"

Forensic Sci Int. 2019 Feb:295:64-71. doi: 10.1016/j.forsciint.2018.11.028. Epub 2018 Dec 6.

Authors

Stephan Christen¹, Hans Rudolf Jordi²

Affiliations

¹ Forensic Institute Zurich, Switzerland. Electronic address: stephan.christen@for-zh.ch.
² Forensic Institute Zurich, Switzerland. Electronic address: HansRudolf.Jordi@For-zh.ch.

PMID: 30572221
DOI: 10.1016/j.forsciint.2018.11.028

Abstract

The Glock company's newest generation of pistols (G42/43, Gen5) is equipped with so-called "Glock Marksman Barrels" (GMB). These barrels feature an enhanced polygonal profile with right-hand twist and a small rifled profile on either side of the main polygonal field impression (Hernandez et al., 2016). Up until now, using the usual methods of comparison (automatic ballistic identification systems, ABIS and comparison microscope) it was difficult to assign bullets fired from a polygonal barrel to their origin with a high evidentiary value (Murdock et al., 1990) [5] (Northcutt, 2010). In this study, test shots from 18 Glock Gen5 pistols (9 Glock 17 pistols and 9 Glock 19 pistols) were compared to examine their differentiability. In addition, a Gen5 Glock 17 pistol was used to shoot 500 cartridges to determine to what degree the first projectile could be matched with the 500th (Zhang and Luo, 2018) [10]. This study was able to demonstrate that the new "Glock Marksman Barrel" (GMB) leaves marks of sufficient quality on projectiles to make high evidentiary value assignments of those projectiles to an individual firearm, both by using the comparison microscope as well as with an ABIS (Evofinder^®). Further, it was possible to assign the cartridge casings to an individual pristine firearm.

Keywords: ABIS; Comparison microscope; Evofinder(®); GMB; Glock Gen5; Glock Marksman Barrel.