The size of the exit wound and the ruptured skull was definitely caused by the explosive exit wound. However, there had to have been a significant piece of the missile to compress the brain matter that exploded out of the front part of the skull. Whether the skull ruptured because of the pressure alone before the bullet struck the skull from the inside or whether it occurred with the exit of that fragment through the skull is probably not possible to determine.
"The fact that the fractures in a skull are due to temporary cavity formation
was demonstrated by a series of experiments with skulls. When skulls were
empty, the bullets 'drilled' neat entrances and exits without any fractures.
When the skulls were filled with gelatin to simulate the brain, massive
secondary skull fractures were produced."
-- Vincent J.M. DiMaio (
Link )
How about this?
- Bullet enters skull at rear, disintegrates by time it gets through the bone
- Bullet hole at rear of skull, with a few fractures radiating downwards
- Fragment from the bullet strikes the inside of the upper-right skull,
causing a regular-sized exit wound hole; not the large gaping wound - Maybe the exiting bullet fragment disintegrated further, with two
pieces causing the strikes on the windshield and windshield frame - Or maybe a sizeable skull fragment did detach, along with the hinged
Devil's Ear opening out; this would allow the unimpeded passage of
other bullet fragments - Exit wound fragment (or following fragment) continues onward to
impact windshield - Fractures extend from the exit opening ("secondary" fractures)
- Temporary cavity formation now occurs within the now-weakened cranium
- Cavity forces large skull fragments to detach along existing skull fractures
and/or new ones caused by the cavity, resulting in the large gaping wound
The only thing I go against in what DiMaio states is that the bullet caused fractures at the in-shoot and out-shoot, while DiMaio says there would have been "neat" holes without fractures.
The pressure impulse from the temporary cavity occurs in the wake of the bullet. Ballistic-wise, the brain is consider a liquid. I'm a layman when it comes to the medical evidence.
