Ten (10) pistol slides with consecutively manufactured breech faces, were obtained from Sturm, Ruger Co, Inc. A total of nine (9) test fires from each pistol, for a total of ninety (90) test fired cartridge cases, were compared using comparison microscopy. Additionally, the breech face marks on the cartridge cases were analyzed using confocal microscopy combined with three dimensional cross correlation analysis algorithms. There was no overlap of cross correlation scores between matching and non-matching test fires. This provides objective data that supports the theory that microscopic impression toolmarks produced on fired ammunition such as breech face toolmarks are reproducible and can be used to both distinguish and associate fired cartridge case evidence to particular firearms.
Citation: Journal of Forensic Sciences
Pub Type: Journals
Confocal Microscopy, Ballistics, Breech Face, Toolmarks, Cross Correlation Function, Firearms