Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol
Abstract Background The forms and compositions of primer gunshot residue (GSR) in shooting cases have been routinely analyzed in many crime labs by scanning electron microscope/energy-dispersive X-ray spectroscopy (SEM/EDS). Gunshot residue studies over the last 30 years have identified a contributi...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2023-03-01
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| Series: | Egyptian Journal of Forensic Sciences |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s41935-023-00326-5 |
| _version_ | 1827982935139024896 |
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| author | Bryan R. Burnett Felice Nunziata |
| author_facet | Bryan R. Burnett Felice Nunziata |
| author_sort | Bryan R. Burnett |
| collection | DOAJ |
| description | Abstract Background The forms and compositions of primer gunshot residue (GSR) in shooting cases have been routinely analyzed in many crime labs by scanning electron microscope/energy-dispersive X-ray spectroscopy (SEM/EDS). Gunshot residue studies over the last 30 years have identified a contribution by residual GSR from surfaces within the firearm to GSR (the “memory effect”). In this study, we first focus on the GSR compositional differences between target, bore, and cylinder gap for a .22 caliber revolver which has received little attention in the literature. Secondly, we examine the behavior of elements involved in the residual contribution to GSR for a .22 caliber pistol. Results The compositions of target, bore, and cylinder gap GSRs from a .22 caliber revolver were determined for 11 discharge series. Breech GSR compositions from a .22 caliber pistol changed in sequential discharges revealing behavior of individual primer and bullet elements. The target GSR forms from some .22 caliber ammunitions were not spherical. Conclusions For the revolver, GSR compositions from the target, bore, and cylinder gap are divergent. Analysis of the pistol’s breech GSRs indicated mixing with the previously deposited GSRs resulting in a sequential contribution or loss of elements and redeposition of the new composition. Aluminum did not contribute to the residual GSR. The GSR composition of a discharge and its contribution to residual GSR on the internal parts of the firearm represents a complex process which likely involves a number of variables including, but not restricted to firearm design, primer composition, pressure and temperature of the discharge gas, and bullet surface composition. |
| first_indexed | 2024-04-09T22:39:47Z |
| format | Article |
| id | doaj.art-d8730e370bbd4b50a7a5a43adb832651 |
| institution | Directory Open Access Journal |
| issn | 2090-5939 |
| language | English |
| last_indexed | 2024-04-09T22:39:47Z |
| publishDate | 2023-03-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Egyptian Journal of Forensic Sciences |
| spelling | doaj.art-d8730e370bbd4b50a7a5a43adb8326512023-03-22T12:15:04ZengSpringerOpenEgyptian Journal of Forensic Sciences2090-59392023-03-0113112010.1186/s41935-023-00326-5Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistolBryan R. Burnett0Felice Nunziata1Meixa TechMathematics and Physics Department — Università degli Studi della Campania LUIGI VANVITELLI Viale Lincoln No. 5Abstract Background The forms and compositions of primer gunshot residue (GSR) in shooting cases have been routinely analyzed in many crime labs by scanning electron microscope/energy-dispersive X-ray spectroscopy (SEM/EDS). Gunshot residue studies over the last 30 years have identified a contribution by residual GSR from surfaces within the firearm to GSR (the “memory effect”). In this study, we first focus on the GSR compositional differences between target, bore, and cylinder gap for a .22 caliber revolver which has received little attention in the literature. Secondly, we examine the behavior of elements involved in the residual contribution to GSR for a .22 caliber pistol. Results The compositions of target, bore, and cylinder gap GSRs from a .22 caliber revolver were determined for 11 discharge series. Breech GSR compositions from a .22 caliber pistol changed in sequential discharges revealing behavior of individual primer and bullet elements. The target GSR forms from some .22 caliber ammunitions were not spherical. Conclusions For the revolver, GSR compositions from the target, bore, and cylinder gap are divergent. Analysis of the pistol’s breech GSRs indicated mixing with the previously deposited GSRs resulting in a sequential contribution or loss of elements and redeposition of the new composition. Aluminum did not contribute to the residual GSR. The GSR composition of a discharge and its contribution to residual GSR on the internal parts of the firearm represents a complex process which likely involves a number of variables including, but not restricted to firearm design, primer composition, pressure and temperature of the discharge gas, and bullet surface composition.https://doi.org/10.1186/s41935-023-00326-5Gunshot residue.22 caliberRevolverPistolScanning electron microscopy/energy-dispersive X-ray spectroscopyMemory effect |
| spellingShingle | Bryan R. Burnett Felice Nunziata Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol Egyptian Journal of Forensic Sciences Gunshot residue .22 caliber Revolver Pistol Scanning electron microscopy/energy-dispersive X-ray spectroscopy Memory effect |
| title | Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol |
| title_full | Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol |
| title_fullStr | Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol |
| title_full_unstemmed | Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol |
| title_short | Divergent gunshot residues and characterization of the memory effect in a .22 caliber revolver and pistol |
| title_sort | divergent gunshot residues and characterization of the memory effect in a 22 caliber revolver and pistol |
| topic | Gunshot residue .22 caliber Revolver Pistol Scanning electron microscopy/energy-dispersive X-ray spectroscopy Memory effect |
| url | https://doi.org/10.1186/s41935-023-00326-5 |
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