Here's what an ancient sling might have looked like.
"Slingers are often visualized as releasing overhead, yet the best way to utilize a sling is by an underhand motion, like a softball pitcher," said Grace Kellner, Artifacts Registrar of the Kh. el-Maqatir excavation. "Elaborate wind-ups were wasted motion. One windup, like a good softball pitcher, was sufficient. - taken from http://www.biblestudysite.com/arch.htm
Since the Shelbys were over today while Amy went to her 1st OB appointment, we decided to make the slings that were suggested in our Old Testament Days book.