Abstract: The performance of 7.62×54r BS32 armour-piercing incendiary (API) projectiles against ceramic-faced armour is investigated in trials for yawed impacts. Controlled yaw of the projectile was induced by chamfering the rear of the projectile, producing strong asymmetric lift forces on the tail of the round during the intermediate ballistics phase. High-speed video recorded yaw in two orthogonal planes immediately before impact. Projectile yaw varied in a sinusoidal manner at approximately 3.5m wavelength with a maximum of 8-14 degrees at approximately 10m from the muzzle. Logistic regression was used to determine the penetration probability curve and V50 ballistic limit velocity which was found to be 735 m/s for the un-yawed projectiles but only 685 m/s for the yawed projectiles.