Terminal Velocity

In ballistics, terminal velocity is the speed the bullet has left at the moment it strikes, which is simply the retained velocity measured at the target distance. It matters because impact speed sets the kinetic energy delivered, and energy scales with the square of velocity, so even a modest loss of speed downrange takes a large bite out of what arrives. This is the number that separates a bullet that performs on target from one that simply arrives with too little energy left.

Terminal velocity also governs how the bullet behaves on contact. Most expanding designs need a minimum impact speed to open reliably, and below that threshold expansion becomes inconsistent or fails. As distance grows the bullet slows toward the transonic range, where both stability and terminal performance can degrade, which is why knowing the impact speed at a given range is as important as knowing the drop.