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Penetration performance of protective materials from crossbow attack: a preliminary study.
James Read1, Rachael Hazael1, Richard Critchley2
1Defence Academy of the United Kingdom, Cranfield Forensic Institute, Cranfield University, Shrivenham, SN6 8LA, UK.
Forensic Science, Medicine, and Pathology
|March 13, 2023
Summary
Broadhead crossbow bolts can perforate protective materials at high velocities. While some bolt types are not lethal, advanced materials show effectiveness against crossbow threats, necessitating further armor development.
Area of Science:
- Ballistics
- Materials Science
- Forensic Biomechanics
Background:
- Increasing crossbow injuries necessitate research into bolt lethality and protective material failure modes.
- Limited data exists on the effectiveness of protective materials against various crossbow bolt designs.
Purpose of the Study:
- To experimentally validate the lethality and material failure effects of four different crossbow bolt geometries.
- To assess the performance of two distinct protective mechanisms against crossbow projectiles.
Main Methods:
- Testing four crossbow bolt geometries against para-aramid and polycarbonate composite armor.
- Measuring projectile velocity and observing material failure modes upon impact.
Main Results:
- Ogive, field, and combo tips at 67 m/s did not cause lethal effects at 10m.
- A broadhead tip perforated para-aramid and polycarbonate armor at 63-66 m/s.
- Armor layering and polycarbonate "petalling" reduced projectile velocity, indicating material effectiveness.
Conclusions:
- Specific bolt geometries pose a significant threat, capable of perforating tested protective materials.
- Current protective materials demonstrate effectiveness, but velocities approach overmatch limits, highlighting the need for advanced armor development.
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