Trashgun
This weapon was made using the finest materials in local dumpsters. Add 3 UNRELIABILITY points.
Slam guns are improvised firearms which consist of two tubes and a firing pin. When the user slams one into the other, a shotshell is fired in the general direction of the enemy. This is literally the simplest type of firearm possible, more so than muskets or even fire lances. PVC and lead pipes aren't particularly known for their material resistance, so most of these weapons are chambered in 20-gauge instead of more powerful shotshell calibres.