Armour-piercing discarding sabot higher muzzle velocity. Unfortunately the low sectional density of the APCR resulted in poor carrying power (high aerodynamic drag), losing velocity and penetration rapidly over distance. To overcome these limitations the British devised a way for the outer sheath to be discarded after leaving the bore. The name given to the discarded outer sheath was the sabot (a French word for a wooden shoe). For APDS projectiles the sabot is also known as a pot, as the sabot resembles a flower pot in shape. The APDS has the advantages of the lightweight projectile with regards to bore acceleration and high
Armour-piercing discarding sabot in combination with the sub-projectiles' higher sectional density, gives the resulting sub-projectile vastly reduced aerodynamic drag in comparison to the APCR. Both the higher initial velocity and the reduced drag result in high velocity at impact. This also lowers flight time and improves accuracy. Accuracy can suffer if there are unwanted sabot/sub-projectile interactions during discard. The sequence upon impact of the APDS projectile, for example the 120 mm L11, as used on the Chieftain tank, fired L15 APDS (muzzle velocity 1370 m/s), goes as follows: the lightweight ballistic cap is crushed, the penetrating cap then strikes the armour, distributing the