The present study investigates the effects of in bore-yaw phenomenon on lateral throw-off and aerodynamic jump behavior for small caliber rotational symmetric (both in configuration and mass distribution) projectiles launched horizontally at supersonic firing speeds and various altitudes from high-subsonic air vehicles. The ammunition used is the caliber .50 API M8 bullet type firing from M2 machine automatic gun. The projectile is considered to be eccentrically engraved, tilted as it enters the rifling, and it is assumed that the tilt persists throughout its passage through the rifled barrel of the used weapon system. The modified linear 6-DOF flight simulation modeling is applied for the bullet free-flight trajectory predictions. The coupled epicyclic pitching and yawing motion analysis for the first 100 m of the examined trajectories are taken into account.