Ortho-Tron Projection Rod
Definition
A commercial trajectory rod system manufactured by Sirchie, widely used by the FBI Evidence Response Team and forensic laboratories internationally, providing standardised diameters and mounting hardware for wound-channel insertion.
- Manufacturer
- Sirchie
- Use
- Bullet trajectory reconstruction
- Users
- FBI Evidence Response Team and forensic laboratories internationally
- Function
- Standardised rod inserted into a wound or bullet path channel
Common questions
Why is a standardised commercial rod system preferred over improvised rods for trajectory work?+
Standardised diameters and mounting hardware ensure the rod fits the defect without artificially widening or distorting the channel, and consistent equipment across agencies makes trajectory measurements comparable and defensible when different examiners or laboratories are involved in the same case.
Does inserting a trajectory rod risk altering the evidence it is meant to measure?+
Improper insertion can widen or deform a bullet hole, so rods are used only after the defect has been fully documented and measured, and examiners select a rod diameter appropriate to the hole to avoid forcing the channel and introducing a false trajectory angle.
Related terms
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- Ricochet
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