It depends on what they spine out to and the draw weight, draw length, and handle design of your bow. Generally, the more weight you put on the front, the less the functional spine of the shaft is. Also, making the shaft longer decreases the functional spine. So if your arrows are spined right, you would need to shorten them some if you put a heavy point on so that they don't end up spining too weak, or vice versa if your shafts are stiffer than they should be. Just experiment until they are the weight you want and fly like you want them to.