Possible Toolmarks

The marks produced on cartridge cases and shotshell cases during the cycle of fire may include:

Toolmark	Description	Image
Firing pin impressions	Indentation of the primer of a centerfire cartridge case or the rim of a rimfire cartridge case when struck by the firing pin
Firing pin drag marks	Striated toolmarks produced when a projecting firing pin contacts a cartridge or shotshell during extraction and ejection
Breech face marks	Negative impression of the breech face of the firearm found on the head of the cartridge case and/or primer after firing
Primer shearing marks	Striated toolmarks caused by the rough margins of a firing pin hole (aperture) scraping the primer metal during unlocking of the breech of a firearm
Chamber marks	Individual microscopic marks placed on a cartridge case by the chamber wall as a result of chambering, expansion during firing or extraction
Extractor marks	Striated toolmarks produced on a cartridge or cartridge case from the operation of an extractor (usually found on or just ahead of the rim)
Ejector marks	Toolmarks produced on the head of a cartridge case, from contact with the ejector (generally at or near the rim)
Anvil marks	Microscopic marks impressed on the forward face of the rim of a rimfire cartridge case as it is forced or compressed against the breech end of the chamber by the firing pin
Ejection port marks	Striated marks produced by hard contact between the ejection port of a firearm and a rapidly moving ejected cartridge case
Magazine marks	Striated marks produced on the periphery of a cartridge as it moves from the lips of a magazine towards the chamber during feeding

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