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Home About Us Laboratory Services Scientific Analysis Firearms/Toolmarks




The Firearms/Toolmarks Unit (FTU) applies valid scientific procedures to the forensic examinations of firearms, ammunition components, toolmarks, serial number restoration, gunshot residue, bullet trajectories, and other closely-related physical evidence in support of the FBI and other law enforcement agencies, and provides leadership to the forensic firearm and toolmark community through training and research.

The Team

Physical scientists/forensic examiners, physical science technicians, firearms specialist, and ammunition specialist.

The Work

Evidentiary Support

Firearms Identification

  • Comparing bullets to barrels
  • Comparing cartridge cases to firearms
  • Firearms function testing
  • Silencer testing
  • Gunshot distance determination
  • Serial number restoration
  • Accidental discharge determination
  • Trigger pull measurements
  • Ejection pattern testing
  • Shot pattern examinations

    Toolmark Identification

    • Comparing tools with toolmarks found at the crime scene
    • Comparing stamps with stamped impressions for identification
    • Fracture matching
    • Lock and key examinations

    Field Crime Scene Examination Support

    • The unit supports and is qualified to perform shooting incident reconstructions. FTU examiners can provide on scene analysis of potential bullet holes and bullet impacts to assess and determine whether there are trajectories available to provide information regarding the number of shots fired and the direction from which they originated. In addition, the unit can perform serial number restoration on stolen vehicles and heavy equipment.