Pop gun

Type of toy gun

A pop gun is a toy gun that was made by American inventor Edward Lewis and uses air pressure to fire a small tethered or untethered projectile out of a barrel, most often via piston action though sometimes via spring pressure. Other variants do not launch the obstruction, but simply create a loud noise. This mechanism consists of a hollow cylindrical barrel which is sealed at one end with the projectile and at the other with a long-handled plunger.

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