AFTE Store - Cartridge Case Sidewall Markings from Ejectors of Glock Pistols

Glock pistols and cartridge cases fired in them are often received for forensic firearms examination. These pistols have clearly defined class characteristics, including two distinct firing pin aperture shapes – rectangular and tear drop. The first shape is typical of older generation pistols, which includes most of the models of Generation 4, whereas the second shape is typical of Generation 5 pistols. Similar class characteristics can be found on cartridge cases fired in Smith & Wesson pistols from the Sigma and M&P series. Therefore, it is essential to describe the marks which can be used to distinguish between pistol from different Glock generations and pistols from various manufacturers. During the examination of hundreds of Glock pistols of different models and cartridge cases fired in and cycled through these firearms, a specific mark produced by the ejector of Glock Generation 4 and 5 pistols was observed. This article describes the source of this mark and its shape. The possibility of using this mark as a class and/or individual characteristic is investigated and discussed.