I have a movie clip I need to scroll infinitely from right to left, seamlessly.

In the first frame I have:

Code:
moveAmt = 40;
stop();
I then have two instances of one movieclip on the stage, "strip" and "strip2". On "strip" the following clip actions are applied:

Code:
//initialize
onClipEvent (load) {
	percent_increment = .075;
	addstrip2 = false;
}
onClipEvent (enterFrame) {
	this._x -= (_root.moveAmt)*percent_increment;
	//
	if (this._x<=0 && this._x>=-this._width) {
		_root.strip2._x = this._x+this._width-1;
		_root.strip2._y = this._y;
		trace("step 1");
	}
	if (this._x<=-this._width) {
		this._x = _root.strip2._x+this._width-1;
		trace("step 2");
	}
	if (this._x>0 && this._x<this._width) {
		_root.strip2._x = this._x+this._height-1;
		_root.strip2._y = this._y;
		trace("step 3");
	}
	if (this._x>=this._width) {
		this._x = _root.strip2._x-this._width+1;
		trace("step 4");
	}
}
They both scroll from right to left without a hitch, but then stop and don't loop like they should. What am I doing wrong?

Thanks in advance.