Ballistic trauma and damage result from the transfer of kinetic energy from a projectile to the body or target, which depends on the firearm, the load, the geometry of the projectile, and how the projectile interacts with the target. If a projectile penetrates the body, the body is cut immediately due to high stresses at the tip of the projectile and also stretched as the energy transferred from the projectile temporarily moves muscles or organs away from the projectile’s path. If a projectile has enough energy, the transfer of energy may also initiate a shock wave with potential to cause additional injury and/or faster incapacitation. Injuries due to projectiles from small arms also include blunt trauma, for example, when a projectile strikes body armor but does not penetrate, or when less lethal munitions are involved. Body armor may absorb some energy but also causes the transfer of energy to the body to be spread out over a larger area; injuries ranging from minor bruising to life-threatening organ damage can still result.

Exponent’s scientists, medical professionals and engineers apply the physics of small arms ballistics to solve a variety of research and real-world problems, and to assess ballistic-related issues related to a specific incident.  For instance:

  • Was a suspected shooter standing next to that car when bullets entered the building across the street? 
  • How was a projectile changed by passing through that window (or door, or wall)? 
  • How fast might someone be incapacitated (or not) if shot with a specific bullet? 
  • Can a bullet break a bone without directly hitting it? 
  • What does it really mean when I read that equipment meets a specific National Institutes of Justice (NIJ) standard? 
  • Can we design a projectile to be safely used in wildlife management in urban   settings? 
  • Can service dogs benefit from body armor?

Exponent’s staff reconstructs incidents involving injuries from small arms and conducts research on specific terminal ballistics performance or personal protection equipment for domestic, law enforcement, and military applications. Our staff combines expertise in forensic pathology, biomechanics, ballistics, and human factors, to conduct incident reconstructions and to evaluate protective equipment. 

Photograph of clay imprints demonstrating protective performance of body armor (left: 8 layers Kevlar, right: 15 layers).


Our capabilities include:

  • Expertise in mechanisms of ballistic injuries
  • Expertise in the biomechanics of body armor and behind armor ballistic trauma (BABT)
  • Ballistic range testing capabilities
  • Knowledge of small arms physics including internal, external and terminal ballistics of small arms

We provide in-person short courses which can be customized to cover basic safety, operation and physics of firearms, or to address specific applications such as understanding less-lethal munitions, selecting ammunition or protective equipment for specific purposes, or investigating events involving firearms.

If your organization already has the technical knowledge and skill, but not the time or staff, Exponent has the capabilities, knowledge and experience to support your product development. Exponent staff can help you develop a patent application, investigate whether your patent has been infringed, prepare a white paper summarizing the state of the science or art, development and review test plans to applicable standards, and assist in technical aspects related to funding applications.