Hollow-point ammunition and handguns: The potential for large temporary cavities

Abstract

In the civilian setting, gunshot wounds are usually secondary to handguns. Wound ballistics for handgun bullets are notable for low velocities and low kinetic energy; as a result, these bullets are thought to only injure tissues that are directly in their path. This bullet tract is called the permanent cavity. In contrast, high velocity rifles can also create temporary cavities; the kinetic energy imparted by these bullets is propagated as hydrostatic force that displaces tissue forward and radially, producing a temporary displacement of tissues. This temporary cavity may be considerably larger than the diameter of the bullet, but rarely lasts longer than a few milliseconds before collapsing back into the permanent cavity. We describe a case where a patient presented with a large pulmonary contusion that was secondary to the temporary cavity caused by a tangential handgun wound to the chest. In this case, the gunshot wound was caused by a calibre .40 handgun using hollow-point ammunition. Some consideration, however, should be given to the type of handgun and ammunition used. Large calibre handgun bullets may also cause large temporary cavities. In addition, hollow-point bullets may also contribute to a large temporary cavitation effect. Hollow-point bullets are designed to rapidly deform upon entering tissue, thereby becoming unstable. As a result, these bullets tend to disintegrate upon contact, remain within the target, and impart all of their kinetic energy to the surrounding tissue.