Armor-piercing discarding sabot (APDS) is a type of spin-stabilized kinetic energy projectile for anti-armor warfare. Each projectile consists of a sub-caliber round fitted with a sabot. The combination of a lighter sub-caliber projectile with a full-caliber propellant charge allows for an increase in muzzle velocity compared to full-caliber rounds, giving the round increased armor-penetration performance. To further enhance their armor-penetration capabilities, APDS rounds typically feature a hardened core made from tungsten or another hard, dense material.
For a given caliber, APDS ammunition can effectively double the armor penetration of a gun when compared to full-caliber rounds such as AP, Armor-piercing Capped (APC), and Armor piercing Capped Ballistic Cap (APCBC) projectiles.[1]
APDS-rounds were commonly used in large caliber tank guns up until the early 1980s, but have since been superseded by armor-piercing fin-stabilized discarding sabot (APFSDS) projectiles, which use fin-stabilization and can be fired from smoothbore guns.[2] APDS rounds remain in use for small or medium calibers, such as in saboted light armour penetrator (SLAP) ammunition.[3]