Bullet isn't moving forward

 var weapon : Transform;
 var tranq : GameObject;
 var bullet : GameObject;
 var Speed : int = 5000;
 var fwd;
 
 function Start(){
  fwd = transform.TransformDirection(Vector3.forward);
  }
 function Update () {
 transform.position = weapon.TransformPoint(Vector3.zero);
 transform.forward = weapon.TransformDirection(Vector3.forward);
 }
 
 function ShootTranq(){
 var tranqClone = Instantiate(tranq, transform.position, transform.rotation);
         tranqClone.rigidbody.AddRelativeForce(fwd * Speed , ForceMode.Impulse);
 
 
 }

The bullet gets instantiated but it never moves? How do I fix this?