The watermelon shot is head on. The bullet penetrates the hard unyielding shell of the watermelon and as it does so, the shock waves have to go somewhere. But the shell is unyielding, so the shock waves ripple around and where the shell is thinner and weaker it breaks up. In the mean time, the bullet is penetrating into the interior which is also solid, inflexible, though it is deliciously crunchable. But the waves travelling through the interior also set up stresses that get resolved at weak points. Overall result is that the watermelon absorbs a lot of the energy of the bullet and explodes.
The ear shot is NOT head on. The ear sticks out and is barely nicked by the bullet. It is like the difference between shooting a 4 mm thick leaf and shooting a watermelon.
The ear is not brittle like watermelon or a head. It is based on flexible cartilage. Challenge it, and it gets knocked aside. The flexibility means that the energy is absorbed by the movement of the ear and not transmitted. Plus the shot was front to back, so the ear easily moves. The other way there would have been more damage but definitely nothing like an exploding skull.
The ear shot transfers very little energy into a nick. It takes a chunk out because it does have energy, but that chunk is not pushed deeper into the watermelon or head transferring energy as it goes. The earlobe is thin, like about 4 millimeters.
There is not much "there" there in an earlobe. Only idiots and hagiographers believe he was shot in the face. To post an exploding watermelon is to accept the "shot in the face" narrative.
1) Trump was not shot in the face on like the watermelon video.
2) Ears are flexible unlike watermelons.
3) Ears are thin unlike watermelons or heads behind faces.
4) The bullet was photographed in flight after it nicked his ear.
It is necessary to analyze these things more deeply than just a "oh head shots make heads explode" first take.
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