When I was a little kid, my Friends and I used to make slings out of old leather shoe, and boot tongues. Don't know how accurate we were but as well as I can remember I think we could come pretty close to what we were throwing at, but our main goal was just distance, and how large of a rock we could fling out there. It was fun. I have been thinking about making some again. Got lots of room, and rock in Montana.
At the huckleberry festival in Trout Creek, Mt., I met a Japanese woman who was doing fingerweaving, and she said she would teach me how to finger weave. So I will have to look her up, and then see if I can make a woven sling. I also have to get another book on Macrame, and try to make one that way also.
Wayne