I'm rather annoyed Mythbusters wasted an entire episode on Bugs Bunny. I mean, Golly-geen folks, if you put a finger in the barrel of a gun to stop the bullet, Darwinism selected you to die before procreating, thus preventing your "stupid" genes from infecting the next generation.
All you have to do is look at spiked cannons, or spiked gun barrels. It doesn't stop the bullet, it just ruins the gun. Hell even the Mythbusters spiked the tree trunk cannon, and saw it vaporize itself (granted with far too much black powder).