localposition not working? Calculating a vector in front of an object. Picture and code included

I am making a 3D spaceship combat minigame.

I need to launch a projectile from my spaceship, towards a position that is the targeted enemy position, adding 30 or something to the local Z of that position (i.e, "shooting it ahead of the enemys forward path), but I need to be grabbing that vector when the shot is instantiated, so that it is traveling in a straight line (interpolating / following / lookat is not what i need).

Here is what I have, and it is working as coded, but the calculation that adds to the Z position ends up giving me a vector that is higher than the Z axis value in the world space, despite me using localposition. what I need is, that vector to end up as higher than the ships Z axis value, so it is "In front of where the ship / target" was at the moment of that calculation.

     void Start () {
         player = GameObject.FindWithTag ("Player").GetComponent <Player> ();
         Destroyshot ();
         hasTarget = player.seesTarget;
         if (hasTarget) {
 
             target = player.locktarget;
             targetahead = new Vector3 (target.localPosition.x, target.localPosition.y, target.localPosition.z + 30);
             transform.LookAt (targetahead);
 
         }
     }
     
 
     void Update () {
 
         gameObject.transform.Translate (Vector3.forward * speed);
         Debug.DrawLine (gameObject.transform.position, targetahead);
 
     }