There has always been something about sling shots I liked. I haven’t had one for a very long time though. It seems from your comments that the Barnett model needs some improvements. Are there other commercial sling shots for sale?
When we were kids we made our own from a Y branch of a hardwood tree. Selecting a branch with the best Y was important. It had to have a relatively narrow angle between the branches, guessing it would be about 30`. Then we used the biggest thick rubber bands we could come up with. The tongue of an old shoe made a great pouch. We would saw a slot in the top of each Y leg to slip the bands into, then just tie a knot in the end to prevent the bands from pulling through. I never made one with a wrist support but I guess It wouldn’t be to hard to figure figure out.