I'm just guessing here, but it looks to me that those would screw into the end of a target practice arrow shaft (as in a bow and arrow). The screw allows for the tip to stay attached to the shaft and the straight shank provides alignment. Last thing you'd want is misalignment because it would make the arrow not fly true. It isn't a hunting tip because a pointy tip won't cause alot of tissue damage and blood letting (sorry)....
RE: Calling All Tool Nerds! WTF Is This? - #11