I am not much of a gun enthusiast, so I had to think a bit about this theme.  I saw my daughter eating a banana, and it brought back memories of my boys when they were little.  Invariably, when they first grabbed a banana, they would hold it like a gun, and pretend to shoot.  As I had a few teenage boys on hand;  my younger son on spring break and his friends, I enlisted their help for this theme:

The background is a photoshop modified google image of the movie Gunfight at O.K. Corral, and  the grunge frame is from HG Designs.