Pumpkin' Chunkin' and other non-standard weapons

[Olefin]

Saw this post

Going even further back, just YouTube Pumpkin' Chunkin' and take a look at the power of ancient siege engines. If an air cannon can launch an EIGHT POUND PUMPKIN OVER A KILOMETER, it can launch an 8lb rock too. Look at the Trebuchet's power in use. In fact, one weapon I have considered making is a modern version of a Ballista using truck leaf springs. Imagine 4 leaf springs stacked on what would be, in essence, a crossbow on steroids that fired a 6-foot metal spear. You would use a come-along/winch to cock it and the bowstring would be 10 gauge wire like the stuff used in skyscraper antenna guidewires. I'm willing to bet that it could shoot that 6ft "bolt" completely through a modern passenger car. Primitive does NOT mean ineffective.

Has anyone ever included weapons like this in a campaign?