[Double Tap]

When the hero of a horror flick does use a firearm to stop the bad guy/monster, they will then drop/throw down the gun in disgust, only to have the same bad guy/monster attack again.

[Rocko]

Multiple Freepers will post the same idea within the same three minutes.

[steve-b]

In the old Superman TV show, the villians would shoot at Superman, he'd stand there as the bullets bounced off, the villians would thrown their guns at him in disgust, and he'd duck.