A blunderbuss is a muzzle-loading black-powder firearm. It can fire shot (a packet of small metal pellets), but can also be loaded with gravel, sand, or whatever else is at hand that can fit in the muzzle. When loaded with improvised ammunition in this way, the blunderbuss deals 2d4 piercing or bludgeoning damage.
2d6 piercing, ammunition (range 20/80), misfire 3, reload 1, scatter, two-handed