- 01: Introduction
- 02: History
- 03: Propellants, Firearms, and Ammunition Development
- 04: Modern Firearms Manufacture
- 05: Small Arms Ammunition
- 06: Evidence Handling Procedures
- 07: Equipment and Instrumentation
- 08: Examination of Firearms
- 09: Cartridge and Shotshell Examination
- 10: Characterization and Evaluation of Fired Projectiles
- 11: Bullet Comparison and Identification
- 12: Gunshot Residue and Distance Determination
- 13: Toolmark Identification
- 14: Communicating Results
- Resources
Examination
Home > Examination of Firearms > Examination
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Split barrel resulting from
incorrect ammunition
The following preliminary steps in the examination of all firearms should be sequenced according to laboratory protocol and be documented:
- Ensure that the firearm is unloaded.
- Determine the brand and model.
- Determine caliber designation.
- Measure the bore diameter.
- Measure the chamber, if possible.
- Research the type of design.
- Determine the country of origin. (Many of the older bolt-action rifles were manufactured for various countries, each of which used a different type of military ammunition).
- Obtain the cartridge dimensions by casting the chamber, if necessary.
- Determine the action type.
- Determine the safety type.
- Determine if any modifications or alterations have been made.
(AFTE Journal can be searched by keyword) - Observe anything else unusual about the firearm.
- Note the type of sighting system and any accessories present.
- Examine the bore (interior of the barrel) and determine class characteristics (number of lands and grooves and direction of twist).
- Examine the interior of the bore to ensure it is free of projectiles.
- Check the bore for the possible presence of biological material or gunshot residues. If biological residues are present, notify the proper laboratory section.
- Check for bulges or damage to the bore.
- Examine the chamber and/or forcing cone area for damage or cracking.
In addition, all firearm examinations include testing the trigger pull, the safety feature, and test firing of the mechanism.
Click here to read a sample forensic worksheet and report - Firearms
