austin wrote:A bullet is not round. It is long and it spins.
When it hits something, the resulting linear momentum change causes the bullet's center of rotation to change which is resisted by the bullet's angular momentum which is resisted by the object the bullet has come in contact with which pushes back on the bullet.
This does all sorts of things, one of which is the angle of incidence does not match the angle of reflection.
Lead flattens, absorbing the impact and diminishing the reflect angle. Tt does not rebound as rubber might. But rubber bullets rebound!!