I found a good way to chop a chicken's head off without you having to worry about it moving and you missing. Just take two framing nails and hammer them into a stump close together but on an angle so they form a V. Then you slide the neck in between the two nail and pull slightly on the legs for a little tension. This keeps the bird still while you quickly and painlessly chop off its head. Then dunk it in a pail of water quickly where it can flap and not bruise the meat. Hope this helps with your bird processing next time. Good luck.