- 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
Trigger Weights
Home > Examination of Firearms > Examination > Trigger Pull > Trigger Weights
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trigger weights
Trigger weights are the most commonly used method of determining trigger pull. The system consists of a shaped rod and different sizes of metal weights (usually ¼, ½, 1, 2, and 5 pounds) placed on a flat surface (rest).
The steps in measuring trigger pull with trigger weights are as follows:
- For single-action trigger pull, cock the firearm. For double-action trigger pull, do not cock the firearm.
- Place the trigger under the top portion of the rod.
- Slowly lift the firearm upward with the rod, bringing force on the trigger.
- If the weights come off the rest without the firearm discharging, add more weight to the rod.
- If the firearm discharges before the weights come off the rest, remove weight from the rod.
- Continue until the least weight required to cause the firearm to discharge without the weights leaving the rest is determined.
Click here to watch a trigger pull demonstration
