PHYSICAL EVIDENCE MANUAL - Crime Scene Investigator Network

Physical Evidence Manual
14.0 GUNPOWDER AND SHOT/PELLET PATTERNS
When fired, a mixture of burned and unburned gunpowder, vaporized primer, and
bullet or shot material is blown out the firearm’s muzzle along with the bullet or
shot pellets and wad(s).
Examination of the evidence may reveal the following:
• Proximity, which is the distance from muzzle to target determined by
powder or shot patterns
• Ammunition type
• Ammunition manufacturer
• Firearm condition
• Bullet or pellet entry angle
• Stipling or sooting around the entrance
Collection of Gunpowder Evidence
Submit the clothing or other object(s) that may have gunshot residue or
bullet/pellet holes. Carefully handle and package the evidence to avoid losing
deposited gunpowder and/or other residue(s).
If possible, collect and submit ammunition of the same type used in the crime
(e.g. ammunition from the firearm’s magazine, unused ammunition from a box at
the scene, etc.)
Adopted: May 2002
Revisions: 6
Last Revision: January 31, 2008
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