Changing a Variable in a script from another Object

Hey guys, so i'm aware that this question has been asked a dozen times, but i can't seem to wrap my head around my problem. It's to do with 'Changing a Variable in a script from another Object'. My scripts concept is that you shoot at a crate and it gives you ammunition, the script that gets changed is on the gun's front where the amount of magazines variable 'magcount' is on a script named 'bluewave_shoot.js'. The actual script 'ammobox.js' is attached onto my ammunition box gameobject.

The error i get is:

Here is my code:

 //ammobox.js
 
 var effect : Transform;
 var guntoreload : GameObject;
  
  function OnCollisionEnter(col: Collision){
    if (col.gameObject.tag == "bullet"){
      guntoreload.GetComponent.bluewave_shoot().magcount = 20;
      Instantiate(effect, transform.position, transform.rotation);
      Destroy(this.gameObject, 0.1);
    }
  }

This is 'bluewave_shoot.js':

 //Note: this is one half of the script only (The Public Var is there)
 public var magcount : int = 10;
 var bullet : Rigidbody;
 var power : float = 1500;
 var damage : float = 100;
 var reloadtime : float = 4; 
 var magbulletcount : int = 21;
 var bulletcount : int = 0;
 var otherObj : GameObject;
 public var shootsound: AudioClip;
 private var reloadTimer: float = 0.0; 
 function Start () {
 bulletcount = magbulletcount;
 }
 function OnGUI(){
 if (bulletcount <= 0 && magcount > 0){
 GUI.Label(new Rect (5,20,200,20),"Reloading...");
 }
  else
     GUI.Label(new Rect (5,20,200,20),"Bullet's Left: " + bulletcount);
     GUI.Label(new Rect (5,40,200,20),"Round's Left: " + magcount);
 
 
 }
 function Update(){
     
 if (reloadTimer > 0){ 
 reloadTimer -= Time.deltaTime; 
 if (reloadTimer <= 0){ 
 bulletcount = magbulletcount; 
 magcount--; 
 }
 }

Hope someone can help!

Many Thanks