In order to do some tests for the chest mounted lance thrower, I made a simple handheld launcher for the "arrows" in the fashion of a Hawaiian sling scuba speargun.
Read about it on wikipedia
See a photo of the Hawaiian sling here
Just some TBG rubber (13cm x 5cm x 2,5cm, two bands per side), which gets stretched to about 65 cm. So it is prestreched in undrawn condition.
This is absolutely frightening! The stainless steel tip (made from a 12mm rod) embedds itself deeply into a wooden plank, and flies straight as a ruler. If you shoot it 80 degrees up, it beautifully arches down and sticks in the ground. Nice!
Shot from the chest mounted one, the draw will be much, much harder. But I keep thinking - maybe I need to make a hand weapon based on this little prototype, too.
Once again I am amazed by the power of the rubber-wrap-around attachment. Slippery aluminum tube, direct pull - no give. None.