- 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
- Introduction
- Objectives
- AFTE Knowledge and Ability Factors
- Powders and Residues
- Examination
- Distance Determination
- Significance of Results
- Contact Shot
- Nitrite Residues
- Vaporous Lead Residues
- Residues Consistent with the Passage of a Bullet
- Residues Consistent with the Discharge of a Firearm
- Interpretation Challenges
- Reproduction of Results
- Nitrite Residue Patterns
- Shot Patterning
- Chemical Testing
- Shot Pattern Reproduction
- Selected Bibliography
- 13: Toolmark Identification
- 14: Communicating Results
- Resources
Chemical Testing
Home > Gunshot Residue and Distance Determination > Distance Determination > Chemical Testing
As in the case of performing the chemical processing of suspected bullet holes, processing shot patterns employs the same procedures with a few additional considerations. The Modified Griess Test and the Sodium Rhodizonate Test are performed because a shot pattern may conceal a bullet hole and other residues. The presence of pellet wipe and the lead randomly deposited by the impact of wadding materials would be apparent as a result of testing.
Although it may be possible to detect vaporous lead and nitrite residues as a result of a shotgun discharge at closer ranges, it is typically the shot pattern that is the determining factor for distance.
