Slingshots

Slingshots can certainly be useful tools. David used one to slay Golaith. The Egyptians had whole units of slingers. Over the years the design has gotten more high-tech due to the introduction of elastic rubber as the propulsive force rather than the centrifugal force of slinging the projectile in a large arc before releasing it at the target. In consequence, some have given them other names such as bean shooter. A while back I think I posted on this weapon used by youth gangs in Timor.

Quite something, these utilize the modern elastic force and require, perhaps, a little less skill/practice for effective use.  I bet these could be used for hunting.  However, you'd want to find your dart.  After all, you'd have considerable fabrication time or money tied up in each one. 

One could use lead balls (shot) or nuts (such as go on bolts to become fasteners).  We used nuts from our supply sources together with Wrist Rockets to kill ground squirrels on Fort Hunter-Liggett, CA.  Effective (when contact was made) cheap, silent, concealable and untraceable. 

Rocks as projectiles are a whole different story.  They can be found in appropriate sizes most anywhere.  Rocks cost nothing.  They carry no ballistic information whatsoever (except for the trace they pick up on contact with the target).  Think they aren't viable?   Look at this video of Rufus Hussey and his bean shooter. That is impressive.