A sub-caliber projectile is described for insertion into a projectile receptacle (8) having a projectile head (1) and a tail unit (2) forming guide vanes (4), which engages in a cavity of the projectile head (1). To provide advantageous construction conditions, it is suggested that the guide vanes (4) of the tail unit (2) extend up into the hollow projectile head (1) and the projectile head (1) be folded clamped into the groin area between the guide vanes (4).