Ai Aint Taking Damage From Bullet (FPS Rocket)

hello guys my english isn't that good but im doing my best to explain my problem as best as i can so for start i have 2 scripts the damage reciever and the rocket script both from the fps tutorial well i edited the rocket script a little bit so i would get rid off the explosion area damage and just do damage on hit/collide so i can use it for my ak-47 but it doesn't does any damage and i dont get errors or anything and im stuck on this for about 3 days before those 3 days every bullet with the ak-47 was a one shot kill even if i put the damage to 0 well il show the scripts

THE ROCKET SCRIPT

 var explosion : GameObject;
 var timeOut = 3.0;
 var damage = 10;
 
 function Start () {
 
 Invoke("Kill", timeOut);
 
 }
 
 function OnCollison (hit :Collision) {
     
     
 // Tell the object you hit that it was damaged
 
     hit.CharacterController.SendMessageUpwards("ApplyDamage", damage,SendMessageOptions.DontRequireReceiver);
 
     // And kill our selves
     
 Kill ();
   
 }
 function Kill () {
     // Stop emitting particles in any children
     var emitter : ParticleEmitter= GetComponentInChildren(ParticleEmitter);
     if (emitter)
         emitter.emit = false;
 
     // Detach children - We do this to detach the trail rendererer which should be set up to auto destruct
     transform.DetachChildren();
         
     // Destroy the projectile
     Destroy(gameObject);
 }
 
 
 @script RequireComponent (Rigidbody)
 
 ------------------------------------------------------------
 
 THE DAMAGERECIEVER SCRIPT
 
 
     var hitPoints = 100.0;
 
 var detonationDelay = 0.0;
 
 var explosion : Transform;
 
 var deadReplacement : Rigidbody;
 
 
 
 function ApplyDamage (damage : float) {
 
 
 
     // We already have less than 0 hitpoints, maybe we got killed already?
 
     if (hitPoints <= 0.0)
 
        return;
 
        
 
        
 
     hitPoints -= damage;
 
     
 
     if (hitPoints <= 0.0) {
 
        // Start emitting particles
 
        var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
 
        if (emitter)
 
          emitter.emit = true;
 
 
 
        Invoke("DelayedDetonate", detonationDelay);
 
     }
 
 }
 
 
 
 function DelayedDetonate () {
 
     BroadcastMessage ("Detonate");
 
 }
 
 
 
 function Detonate () {
 
     // Destroy ourselves
 
     Destroy(gameObject);
 
 
 
     // Create the explosion
 
     if (explosion)
 
        Instantiate (explosion, transform.position, transform.rotation);
 
 
 
     // If we have a dead barrel then replace ourselves with it!
 
     if (deadReplacement) {
 
        var dead : Rigidbody = Instantiate(deadReplacement, transform.position, transform.rotation);
 
 
 
        // For better effect we assign the same velocity to the exploded barrel
 
        dead.rigidbody.velocity = rigidbody.velocity;
 
        dead.angularVelocity = rigidbody.angularVelocity;
 
     }
 
 
 
     // If there is a particle emitter stop emitting and detach so it doesnt get destroyed
 
     // right away
 
     var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
 
     if (emitter) {
 
        emitter.emit = false;
 
        emitter.transform.parent = null;
 
     }
 
 }
 
 
 
 // We require the barrel to be a rigidbody, so that it can do nice physics
 
 @script RequireComponent (Rigidbody)

i think the problem is in the rocket script i think the function call of ApplyDamage isn't going good and the weird thing is the real rocket script with area damage and everything works fine i just need the bullet to on hit call function applydamage in the damagereciever and the best thing would be if i can edit the damage in the bullet (rocket script) by a var i tried a bunch of different codes and i just didnt managet to get it fixed

so after 3 days im gonna ask the pro's hope u guys can help me