Recovered Bullets and Projectiles

In an optimum situation, a recovered bullet is relatively intact. It bears physical characteristics due to manufacturing processes and class characteristics produced by the barrel of the firearm from which it was fired.

The examiners report on the fired bullet may include

• descriptive information (e.g., caliber, construction, possible cartridge types, and possible manufacturer),
• general rifling characteristics,
• listing of possible firearms that may have produced the general rifling characteristics,
• evidentiary potential based on individual characteristics present.

However, bullets may be deformed, fragmented, distorted, and possibly unrecognizable. In any form, fired bullets usually produce some useful information that may ultimately contribute to the case.

Fired wadding, pellets, buckshot, slugs, or buffer are not usually identifiable with a particular firearm. However, their class characteristics may provide information about the proprietary design characteristics and dimensional data of the ammunition provided by the manufacturer and/or marketer).

Examination

The following preliminary steps should be addressed prior to any of the case comparisons:

• Review laboratory protocols, as needed.
• Complete administrative requirements.
• Chain of custody.
• Marking of evidence.
• Laboratory case identifiers.
• Investigative file identifier.
• Examiner identity.
• Quality assurance.
• Follow laboratory safety protocols.
• Determine the presence of trace evidence and follow laboratory protocol for collection.
  
  Examples of trace evidence include
  • paint,
  • glass,
  • blood,
  • bone,
  • soft tissue,
  • hair,
  • fibers,
  • wood,
  • metal smears,
  • masonry,
  • stone.
• Determine if latent fingerprint examinations should be performed prior to toolmark examinations.
• Determine if other examinations (not requested) should be performed. If so, coordinate with the investigator.

The examination of fired bullets and projectiles should follow protocols approved by the examiners laboratory, which typically are based upon the Procedural Manual of the Association of Firearm and Tool Mark Examiners (AFTE).

The examination process usually includes the following observations and determinations:

• Bullet weight
• Composition of the bullet
• Base description
• Type and position of cannelures
• Manufacturer/marketer
• General rifling characteristics
  • Caliber
  • Number of land and groove impressions
  • Direction of twist
  • Width of the land and groove impressions
• Bullet design
• Extraneous marks due to firing (skid marks/slippage, shave marks, flared base)
• Suitability for comparison purposes

A worksheet should be completed per laboratory protocol.

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