Pictured is an interesting improvised 9mm firearm being sold within criminal circles in Brazil. The entire trigger group / lower is from a standard paintball marker, allowing for a more useful semi-automatic (open-bolt) operation. A clever feature is the use of standard 9mm holed hexagonal brass bar stock as a crude smooth-bore barrel.

The magazine ‘latch’ is simply a bolt threaded into the magazine-well (turned clockwise to tighten) and It’s cocking handle appears to be a tilt knob from a desk chair.

Full auto only variation:

The ‘Keep Calm and Start Street Sweeping’ award definitely goes to ….