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Firearms Identification, sometimes incorrectly referred to as ballistics can be defined as, "A discipline of forensic science which has as its primary concern to determine if a bullet, cartridge case or other ammunition component was fired in a particular firearm".

Studies have shown that no two firearms, even those of the same make and model, will produce the same unique marks on fired bullets and cartridge cases. Manufacturing processes, use, and abuse leave surface characteristics within the firearm that cannot be exactly reproduced in other firearms.

Under normal conditions, firearms do not change much over time. This allows a firearm recovered months or even years after a shooting to be identified or eliminated as having been used to fire a specific bullet or cartridge case.

Firearms Identification is a comparative examination, where the ammunition components of unknown origin (from the scene of the shooting or body) are compared with bullets, cartridge cases, and shotshells of known origin that have been produced in the laboratory by test firing the suspect firearms. The known and unknown items are compared microscopically using a comparison microscope.


Unique Markings

Microscopic Comparison

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