Evaluating simulant materials for understanding cranial backspatter from a ballistic projectile.

Area of Science:

• Forensic Science
• Physics
• Materials Science

Background:

• Gunshot wounds to the cranium produce backspatter, crucial for reconstructing events.
• Understanding backspatter physics aids in linking projectile evidence to crime scenes.

Purpose of the Study:

• To investigate the physics of projectile backspatter.
• To evaluate simulant materials for skull and skin.
• To assess smoothed particle hydrodynamics (SPH) for modeling backspatter.

Main Methods:

• Impact tests were conducted using various simulant materials.
• Smoothed particle hydrodynamics (SPH), a mesh-free method, was employed.
• High-speed projectile impacts were simulated and analyzed.

Main Results:

• Projectile impact causes site fragmentation and momentum transfer.
• Particles move along paths of least resistance, creating backspatter.
• Medium-density fiberboard outperformed polycarbonate for skull simulation.
• Lorica leather proved superior to natural rubber for skin simulation.

Conclusions:

• Medium-density fiberboard and lorica leather are effective skull and skin simulants.
• Smoothed particle hydrodynamics (SPH) is a viable method for simulating high-speed impact and fragmentation in backspatter events.