Forensic ballistics analysis of an unusual/unrifled/homemade firearm in the absence of the action

ABSTRACT The Directorate of Forensic Science Laboratories, Mumbai-India, has been receiving and examining homemade/desi-katta/improvised firearms for a long time. In all these cases, our work is always focused on the study of various physical parameters, including barrel parameters such as length, weight, the inner diameter of the muzzle end and the breech end. For the current study, we dealt with an interesting case of an unusual/unrifled barrel which was delivered to the Directorate of Forensic Science Laboratories, Mumbai-India, without its frame/receiver or other parts required for normally discharging cartridges (i.e. the hammer, firing pin, trigger, etc.). Without these components, a test firing was done by manually contacting the primer of the chambered cartridge with a ramrod, and comparison microscopy of the exhibit- and test-fired bullets and expended cartridge cases was performed. From the test firing and comparison microscopy, it was concluded from the microscopy results that the test-fired and exhibit-fired bullet and expended cartridge case had been fired from the same firearm, even without the frame/receiver or other part of firearm required for normal operation.