armorpiercing

Armorpiercing refers to projectiles designed to defeat protective armor by penetrating or compromising its integrity. The concept encompasses a variety of ammunition types used against armored targets, from early rifle rounds to modern tank ammunition, and it encompasses both kinetic and explosive approaches.

The most common modern forms are kinetic energy penetrators and directed-jet devices. Kinetic energy (KE) AP rounds rely on a dense, hardened penetrator—typically steel, tungsten, or depleted uranium—surviving impact and concentrating energy to shear through armor. Subcaliber designs, such as APDS (armor-piercing discarding sabot) and APFSDS (armor-piercing fin-stabilized discarding sabot), use a small-diameter, high-velocity penetrator encased in a sabot that sheds after firing. APFSDS ammunition, in particular, is widely used in contemporary tank guns for its high velocity and long-rod penetrators.

Explosive- or jet-based technologies, such as HEAT (high-explosive anti-tank) rounds, use a shaped charge to form a high-velocity metal jet that pierces armor. While not purely kinetic, HEAT rounds are a principal method of armor defeat in many eras and calibers.

Armor itself has evolved from steel plates to composite and ceramic armor, often with reactive layers, making penetration more challenging. Penetration effectiveness depends on impact angle, velocity, and target armor type, with oblique impacts reducing penetration.

Today, armorpiercing concepts remain central to anti-armor weapon systems, particularly in armored fighting vehicles, with continued emphasis on materials science and armor design to counter penetration.