gunshot wounds, that this equates to a range of penetration of 12-18 inches, depending on the size
of the individual and the angle of the bullet path (e.g., through arm, shoulder, etc.). With modern
properly designed, expanding handgun bullets, this objective is realized, albeit more consistently
with some law enforcement projectiles than others.
B. Permanent Cavity
The extent to which a projectile expands determines the diameter of the permanent cavity which,
simply put, is that tissue which is in direct contact with the projectile and is therefore destroyed.
Coupled with the distance of the path of the projectile (penetration), the total permanent cavity is
realized. Due to the elastic nature of most human tissue and the low velocity of handgun projectiles
relative to rifle projectiles, it has long been established by medical professionals, experienced in
evaluating gunshot wounds, that the damage along a wound path visible at autopsy or during
surgery cannot be distinguished between the common handgun calibers used in law enforcement.
That is to say an operating room surgeon or Medical Examiner cannot distinguish the difference
between wounds caused by 35 to AS caliber projectiles.
The temporary cavity is caused by tissue being stretched away from the permanent cavity. If the
temporary cavity is produced rapidly enough in elastic tissues, the tensile strength of the tissue can
be exceeded resulting in tearing of the tissue. This effect is seen with very high velocity projectiles
such as in rifle calibers, but is not seen with handgun calibers, For the temporary cavity of most
handgun projectiles to have an effect on wounding, the velocity of the projectile needs to exceed
roughly 2,000 fps. At the lower velocities of handgun rounds, the temporary cavity is not produced
with sufficient velocity to have any wounding effect; therefore any difference in temporary cavity
noted between handgun calibers is irrelevant. “In order to cause significant injuries to a structure,
a pistol bullet must strike that structure directly."
D. Fragmentation
Fragmentation can be defined as "projectile pieces or secondary fragments of bone which are
impelled outward from the permanent cavity and may sever muscle tissues, blood vessels, etc.,
? Dimaio, VJ.M.: Gunshot Wounds, Elsevier Science Publishing Company, New York, NY, 1987, page 42.
