Improvised firearm

Improvised firearms (sometimes called zip guns, pipe guns, or slam guns) are firearms manufactured other than by a firearms manufacturer or a gunsmith, and are typically constructed by adapting existing materials to the purpose. They range in quality from crude weapons that are as much a danger to the user as the target to high-quality arms produced by cottage industries using salvaged and repurposed materials.

Improvised firearms may be used as tools by criminals and insurgents and are sometimes associated with such groups; other uses include self-defense in lawless areas and hunting game in poor rural areas.