Medieval staff slingers (stern castle). As a weapon, the sling had several advantages; a sling bullet lobbed in a high trajectory can achieve ranges approaching 400 m; Modern authorities vary widely in their estimates of the effective range of ancient weapons. A bow and arrow could also have been used to produce long-range arcing trajectory, but ancient writers repeatedly stress the sling's advantage of range.
'The Sling' A sling is a projectile weapon typically used to throw a blunt projectile such as a stone, clay or lead "sling-bullet". It is also known as the shepherd's sling. ... click through for more info