Blunts kill by blunt force, I guess. Same as a slingshot. As kids we used to cold forge nails into points for arrows and blowgun darts, depending on size. I actually have access to a bunch of barrel hoops which used to be wrought iron. I'm not sure what they are now. Appear to be mild steel. That'd be a good approximation of iron. May gove that a go, but I need a good primitive bow first, so that's the next project.