It's a very simple, easy, and compact design, and it shoots with surprising force.
Now, I was thinking. What if I made a speargun-style slingshot crossbow, but made it so I can slide it into a tube of ABS pipe? If sufficient arrow spine is used, the crossbow could be loaded just like a pneumatic speargun, putting the arrow into the barrel, sticking it's point into the ground, and then using your chest to manually push the setup downwards onto itself, cocking it. The advantage of having everything contained within a barrel is the pure safety of it all, which gives it an advantage to a regular crossbow; unless your hands are in front of the muzzle, nothing will touch you, or hurt you. Another advantage could be stealth. If the rubber itself is contained withing two pieces of pvc pipe, which is contained within some 2'' ABS pipe, and sealed with a whisper biscuit on the muzzle and a wooden dowel on the back plate, I think that the already quiet rubber bands could be even more silenced, possibly creating an ultra stealthy arrow launcher.
Would also just be cool to make, I mean, the velocity probs wouldn't be all that high, but imagine having a huge cannon-looking gun with a broadhead on one end, like a ''Pipe of Doom''
Seems pretty cool to me.
Does anybody else think this would be a cool thing to make?