Fix for Enemy AI script

So, I'm making a 3rd person shooter. I have this script for the Enemy AI which is attached to all enemy characters. The problem is they either all shoot at me fast at once, and kill me instantly. Or, they just follow me around and don't shoot at all. It works pretty crappy. Can any of you savvy chaps fix it?

This is it:

 var projectile : Rigidbody;
  
 var speed = 70;
  
 var player : Transform;
 
  var MoveSpeed = 1;
  
  var MaxDist = 20;
  
  var MinDist = 3;
  
  private var timestamp = 0.0;
  
 function Start() {
     var rendum = Random.Range(1F,3F);
     }
  
 function Update () 
  {
      transform.LookAt(player);
      
      if(Vector3.Distance(transform.position,player.position) >= MinDist){
      
           transform.position += transform.forward*MoveSpeed*Time.deltaTime;
  
                      
           if(Vector3.Distance(transform.position,player.position) <= MaxDist  && (Time.time > timestamp))
  
          {clone = Instantiate(projectile, transform.position + new Vector3(0.0f, 1.5f, 0.0f), transform.rotation);
 clone.velocity = transform.TransformDirection( Vector3 (0, 0, speed));
  
 Destroy (clone.gameObject, 0.5);
 timestamp = Time.time + timestamp;
 } 
 }
 }