I've got a machinegun with 6 "cans", but I'd like to make each can shoot after the other. HELP!!!

The machinegun is this:alt text If u can't see it go to http://www.cringel.com/node/186

Here's my code

var fireRate : float = 0.3;
var delay : float    = 0;
var colpo_fuori : GameObject;// copertura del proiettile
var projectile : Rigidbody;// proiettile che esce dalla canna
var Spawn1: Transform;//
var Spawn2: Transform; //
var Spawn3: Transform;  //
var Spawn4: Transform;  //Le 6 zone dalle quali spara la mitragliatrice
var Spawn5: Transform; //
var Spawn6: Transform;//
var Shoot_Bullet_Speed : int; // velocit dei proiettili
var BulletCount : int; //Ammount of bullets remaining in the clip
var MagCapacity = 999; //The maximum capacity of bullets in the clip

function Update()

{

  if(Input.GetMouseButtonDown(0) && BulletCount >= 1) {

     InvokeRepeating("Shoot", delay, fireRate);

  }

  if(Input.GetMouseButtonUp(0)) {

     CancelInvoke("Shoot");

  }

}

function Shoot() {

  clone1 = Instantiate(projectile, Spawn1.position, Quaternion.identity);
    clone1.AddForce(transform.forward*Shoot_Bullet_Speed);  

    clone2 = Instantiate(projectile, Spawn2.position, Quaternion.identity);
    clone2.AddForce(transform.forward*Shoot_Bullet_Speed);  

    clone3 = Instantiate(projectile, Spawn3.position, Quaternion.identity);
    clone3.AddForce(transform.forward*Shoot_Bullet_Speed);  

    clone4 = Instantiate(projectile, Spawn4.position, Quaternion.identity);
    clone4.AddForce(transform.forward*Shoot_Bullet_Speed);  

    clone5 = Instantiate(projectile, Spawn5.position, Quaternion.identity);
    clone5.AddForce(transform.forward*Shoot_Bullet_Speed);  

    clone6 = Instantiate(projectile, Spawn6.position, Quaternion.identity);
    clone6.AddForce(transform.forward*Shoot_Bullet_Speed);  

}

Well, a chaingun works like any other gun. It always fires only one barrel at a time and always at the same position, usually the topmost. The "ring" of barrels is rotating and only the topmost shoots. It has 6 barrels to prevent overheating since the rate of fire is only 1/6. Do you even rotate your barrels?