Whenever I shoot a bullet from my gun, the bullet disapears.

So I've had this problem for a while now, and have no idea why its happening and how to fix it. Here's a detailed description of what is going on:

So I have first person controller with a gun and an empty object attached to it. The gun is just for show but the empty object, which is placed next to my gun, is what fires bullets (just a sphere and a cube attached to each other). The shooting script, which I found on this website, shoots 14 bullets per second. The script is below:

 #pragma strict
 var bullet : GameObject;
 var bulletsPerSecond = 14.0;
 private var shooting = false;
 function Start() 
 {
     InvokeRepeating("Shoot", 0.0, 1.0 / bulletsPerSecond);
 }
 function Shoot() 
 {
     if (!shooting) return;
     var go = Instantiate(bullet, transform.position, transform.rotation);
     go.rigidbody.AddRelativeForce(Vector3.forward * 1000.0);
 }
 function Update()
 {
     shooting = false;
     if(Input.GetAxis("Fire1"))
     {
         shooting = true;
     }
 }

This script works fine and shoots just the way I want it too, so I don't think that's the problem. This bullet has a rigid body attached to it with gravity off. I also have an AI that has the script below:

 #pragma strict
  
 var Distance : float;
 var target : Transform; //the enemy's target
 var moveSpeed = 1000; //move speed
 var rotationSpeed = 20; //speed of turning
 private var myTransform : Transform; //current transform data of this enemy
 private var controller : CharacterController;
 var lookAtDistance = 25.0;
 var chaseRange = 15.0;
 function Awake()
 {
     myTransform = transform; //cache transform data for easy access/preformance
     controller = GetComponent(CharacterController); // cache the CharacterController
     
 }
 function Start()
 {
     target = GameObject.FindWithTag("Player").transform; //target the player
 }
 function Update ()
 {    
         Distance = Vector3.Distance(target.position, transform.position);
         // find the target direction:
         var dir: Vector3 = target.position - myTransform.position;
         dir.y = 0; // ignore height differences to avoid enemy tilting
         if (Distance < lookAtDistance)
         {
         //rotate to look at the player
         myTransform.rotation = Quaternion.Slerp(myTransform.rotation, Quaternion.LookRotation(dir), rotationSpeed*Time.deltaTime);
         if (Distance < chaseRange)
         {    
             //move towards the player:
             controller.SimpleMove(myTransform.forward * moveSpeed);
         }
     }
 }
 

Whenever the AI is in the scene, my bullet appears for a millisecond, then disappears. Whenever the AI is not in the scene, my bullet works perfectly, so I believe the AI is the problem but I'm just confused. I've tried this with different AI scripts but the exact same thing happens. The AI has a character controller attached to it and these scripts are in javascript.

I have this health script attached to AI as well:

 #pragma strict
 
 var Health : int = 100;
 var bloodPrefab : GameObject;
 
 
 function Update ()
 {
     if (Health <= 0)
     {        
          Dead();
     }
 }   
 
 function ApplyDamage (TheDamage : int)
 {
       Health -= TheDamage;
       }
     
 
 
 function Dead()
 {
 Destroy (gameObject);
 }

Note that the bloodprefab was just a particle system to display blood, but it doesn't do anything yet.

I would be truly grateful if someone knows how to solve this, because this is really irritating me at the moment. Thanks