AttachMovieClip not transfering code?

i made a movie clip and made it so when i clikc on it another movie lip is created inside. That movieclip should move forward but is doesn’t. look at the 10 lines of code and try and find a problem. Heres the code if u don’t want to look at the .fla

on the box:


on (press) {
++i
_root.box.attachMovie(_root.bullet,"bullet"+i,i)
}

on the bullet:


onClipEvent (load) {
this._x = _root.box._x;
this._y = _root.box._y;
}
onClipEvent (enterFrame) {
if (this._name != "bullet") {
this._y -= 5;
}

}