Armour-piercing, capped, ballistic capped shell

By 1910 it was well-established that the aerodynamically optimal form of a solid projectile does not lend itself to best-attainable armour penetration, and remedies were devised.

[2] Early World War II-era uncapped AP projectiles fired from high-velocity guns were able to penetrate about twice their calibre at close range: 100 m (110 yd).

At longer ranges (500–1,000 m), this dropped to 1.5–1.1 calibres due to the poor ballistic shape and higher drag of the smaller-diameter early projectiles.

However, the cap structure of the APC shell reduced the aerodynamic efficiency of the round with a resultant reduction in accuracy and range.

Comparative testing of British 17-pounder (76 mm) gun and US Army APCBC rounds fired into captured German Panther tanks indicated the APCBC munitions were more accurate than late war armour-piercing discarding sabot (APDS) shot, though the lot used was described as sub-standard and the report made no determination of general APDS accuracy.

This type of munition was also designated as APBC (armour piercing ballistic capped), in reference to the Soviet version of APCBC.