AFTE Store - Time Dependent Effects of Decalcification and Formalin Solutions on 9mm Calibre Fired Bullet Striae

Post-mortem examinations of victims of gunshot wounds may involve subjecting the fired bullets embedded in tissue to various chemicals; however, it has not previously been determined if these chemicals degrade the microscopic striae needed for firearm comparisons. A study of the effects of selected chemicals used in pathology examinations on three different 9mm bullet types was undertaken to determine if there is any loss of quality to fired bullet striae when exposed to these chemicals. The bullets were separately exposed to decalcification and formalin solutions for specified timeframes before microscopic comparison to a known (control) sample of each type of fired bullet. It can be concluded that the use of these solutions against full metal jacket (copper) bullets does not have a detrimental effect on the quality of the fired bullet striae, and that identifications are still possible for the range of chemicals used in this project. However, the striae on the 9mm Black Talon SXT® and Silvertip® bullets were degraded during the later stages of the exposure times. These results may be used to assist pathologists and firearms examiners in determining suitable recovery times from tissue.