2 Chronicles 26:14
"And Uzziah prepared for them throughout all the host shields, and spears, and helmets, and habergeons, and bows, and slings to cast stones."
Cross References (ranked by relevance)
1 Samuel 17:49
And David put his hand in his bag, and took thence a stone, and slang it, and smote the Philistine in his forehead, that the stone sunk into his forehead; and he fell upon his face to the earth.
Judges 20:16
Among all this people there were seven hundred chosen men lefthanded; every one could sling stones at an hair breadth, and not miss.