By Andrew Liszewski
While he originally set out to make a simple elastic gun that could fire LEGO bricks Alexie Berteig ended up spending 300 hours on what eventually became a semi-automatic pump-action crossbow.
It holds 4 standard LEGO bricks in the handle with 1 additional brick in the chamber and everytime you ‘pump’ the crossbow the elastic cord is re-tensioned and the next brick is automatically loaded into firing position. When ‘primed’ the entire assembly does exert enough tension to precariously bend some of the LEGO pieces, but so far it has yet to break.
Of course given the lack of any aerodynamic design on the standard LEGO brick the crossbow is not exactly accurate, but it can fire a brick about 20 yards. As the designer puts it “…believe me, you don’t want to fire this thing at the family pet.”
[LEGO Crossbow] VIA [TechEBlog]
I made a lego crossbow once, it shot about 20 meters with slanted blocks and held up to 10 rounds, it was a hassle to get it going though. I have to rebuild one again, I’ve still got some ideas.