Terminal Ballistics
The study of how a bullet behaves on and inside the target, including penetration, expansion, and the energy it delivers on impact.
Terminal ballistics begins where external ballistics ends: at impact. It describes how the projectile penetrates, how much it expands or stays intact, and how much of its kinetic energy transfers into the target. Bullet construction drives most of this, which is why a hollow point and a bonded bullet behave so differently in the same conditions.
Two factors carried over from the bullet’s design matter most here. A high sectional density favors deep, straight penetration, while the jacket and core design control whether the bullet mushrooms, fragments, or drives through. Matching terminal behavior to the intended task is what separates a target bullet from a hunting bullet, even when the two share an identical ballistic profile in flight.