Raycast hitting below mouse position :(

Hello Unity people, i'm making a third person shooter and I'm facing some difficulties figuring out the best way for aiming the gun.

What i did was creating a camera in the hole of the gun that casts a ray to the mouse position, i used Debug.DrawLine to see where the ray is going, and it always goes below the mouse.

This is my script: #pragma strict var rayOrigin : Camera; function Start () {

 }
 
 function Update () {
 var ray = rayOrigin.ScreenPointToRay (Input.mousePosition);
     var hit : RaycastHit;
     if (Physics.Raycast (ray, hit, Mathf.Infinity)) {
         Debug.DrawLine (ray.origin, hit.point, Color.red);
         Debug.LogError("you hit something");
     }
 }

i was pointing at the center of the cube in my game view, but the ray was pointing below it, like in this picture

Help me please