This is where the projectile "spawns" when you shoot, relative to the weapon/soldier position. For example, if the gun is at 0/0/2 and ProjectilePosition is set 0/0/4, then the projectile will spawn at 0/0/6 relative to the vehicle's location. For the Sherman, it is set to 0/0/0 as the the "cannon object" is already positioned at the end of the barrel. On the Mustang, the bomb spawns -0.45 below the "bombdummy", which is located underneath the plane. The -0.45 accounts for the radius of the bomb.
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