removeMovieClip(this);

hi evreyone

I want a MC travel the screen at X pixel per frame (on initialiazing) then when the MC reach an X amount of distance (here 400) get delited from screen

the problem is while the MC does stop running at 400 he dosent disapear from screen staying stuck there

here my code

onClipEvent (enterFrame) {
if(this._x<400){
this._x +=15;
}else{
removeMovieClip(this);
}
}

sorry for this crappy english thx evreyone