We are interested in the effect of a single bullet. Again it is obvious that multiple shots will be more effective, however it is impossible to determine some measure of bullet performance based on multiple shots. In addition, the actual recovered bullets or photographs of the bullets must have been available for examination. Reality shows that frequently the estimated figure turns out to be a little below the actual figure when it becomes available. A bullets most likely effect on a human being is to somehow damage the vascular system.
Bullets cause vascular damage by either severing or tearing blood vessels.
The problem with relying on this mechanism is that it is extremely slow to have an effect. Even if a bullet completely demolishes a persons heart, that person can remain functional for up to twelve seconds, and it is extremely unlikely that a bullet will have such an extreme effect. Usually blood loss is a very gradual process. Disruption of the central nervous system. By far the most effective shot placement is the head area, specifically within the cranial vault or the brain-stem itself.