It appears as though the impacts that just barely puncture the metal actually do the most damage to the object, which I've always read and been told but never been able to visualize why.
It appears that when a bullet punctures the object easily, it conforms very closely to Newton's Impact Depth approximation, however when it barely makes it through it doesn't appear to conform as one of the impacts appears to make a V-shaped wedge through the metal, similar to a hollow-point impact.
It's very interesting to see impact theory when largely it's a science of math and results, it's rare to see the actual impacts (real impacts, IMO shooting fruit on 10,000 fps doesn't count).
It appears as though the impacts that just barely puncture the metal actually do the most damage to the object, which I've always read and been told but never been able to visualize why.
Think of the bullet as a packet of kinetic energy. When the bullet goes through, most of the energy goes through with it. Therefore, the damage to the object is relatively minimal (just a whole).
When it is stopped, however, pretty much all the kinetic energy needs to be dispersed in the object itself. That happens via a number of mechanisms: deformation of the bullet, deformation of the surrounding material, heat, and, if the bullet breaks into pieces, of course, they can each take a chunk of energy with them as they go shooting in every direction.
It appears that when a bullet punctures the object easily, it conforms very closely to Newton's Impact Depth approximation, however when it barely makes it through it doesn't appear to conform as one of the impacts appears to make a V-shaped wedge through the metal, similar to a hollow-point impact.
It's very interesting to see impact theory when largely it's a science of math and results, it's rare to see the actual impacts (real impacts, IMO shooting fruit on 10,000 fps doesn't count).