Experts are often asked what kind of entrance and exit wounds are produced by ammunition. The rounds (bullets) in the photograph below are hollow point bullets similar to the rounds fired from the Thompson sub-machine gun I’m holding in the top photo.
The .45 caliber rounds are about the diameter of the Sharpie pens authors use to sign books. That’s pretty close to the size of most entrance wounds—the size of the bullet.
9mm bullet wound to the chest—close range
Next is one of the .45 rounds after it was fired from the Thompson machine gun.
The round passed through the paper target, through several feet of thick foam rubber, through the self-healing wall tiles of the firing range, and then struck the concrete and steel wall behind the foam. The deformed bullet finally came to rest on the floor. Remember, though, that this all occurred in the blink of an eye, or quicker.
.45 round after striking concrete and steel
Hitting the hard solid surface head-on caused the bullet to expand and fracture which creates the often larger exit wounds we see in shooting victims.
Many times, those bullet slivers break off inside the body causing further internal damage.
The size of an exit wound depends on what the bullet hits inside the body. If the bullet only hits soft tissue the wound will be less traumatic. If it hits bone, expect much more damage. Easy rule of thumb—the larger the caliber (bullet size), the bigger the hole.
Bullets that hit something other than their intended target, such as a brick wall or metal lamp post, can break apart sending pieces of flying copper and lead fragments (shrapnel) into crowds of innocent bystanders. Those flying fragments are just as lethal as as any intact, full-sized bullet.
FYI – Bullets don’t always stop people. I’ve seen shooting victims get up and run after they’ve been shot several times. And for goodness sake, people don’t fly twenty feet backward after they’ve been struck by a bullet. They just fall down and bleed. They may even moan a lot, or curse. That’s if they don’t get back up and start shooting again. And that, writers, is why police officers are taught to shoot until the threat is over.
Simply because a suspect has been shot once or twice does not mean his ability, or desire, to kill the officer is over.