Two objects BOTH with Destroy(other.gameObject) aren't destroying each other??

possibly a newby question here, but.. i've got two bullet objects that, when they hit eachother, won't destroy each other... both have rigidbodies and colliders, one with a tag check,one without any tag checking.. (come at bottom) they both destroy everything else they are supposed to destroy, but when they hit eachother they just bounce and float off.. at first i thought it was from detectcollision, but then they wouldn't bounce, just pass through, so i don't have a clue what's up..

code 1, on "bullet" object tagged "Player"

 function OnTriggerEnter (other : Collider) 
 {
     Destroy(other.gameObject);
     Destroy(this.gameObject);

}

code 2, on "enemybullet" object tagged "Enemy" (yeah i know, real original huh?)

 function update()
 {
  rigidbody.detectCollisions = false;
  if (transform.position.z <= -13)
  {
  rigidbody.detectCollisions = true;
  }
 if (transform.position.z <= -20)
 {Destroy(this.gameObject);}
 }
 
 
 function OnTriggerEnter (other : Collider) 
 {
 
   
    if(other.gameObject.tag=="Player")
    {
     Destroy(other.gameObject);
     Destroy(this.gameObject);
      Debug.Log("EXTERMINATE!");
      AddSingleCubeFab.prevFab =false;
     }
   
 }
 
     i took classes in c++ but my scripting class is using javascript, so i'm learning as i go here, any help would be GREAT!