Arquebus (5e Equipment)
From D&D Wiki
Martial Ranged Weapons
An early firearm and predecessor to the musket, used in the late Medieval period as a supplement to bows and crossbows. It has a long range and high damage, but is very loud and has a reputation for misfires. An alternative to bows in Medieval-era campaigns without getting too anachronistic, it performs largely the same role as the Heavy Crossbow, but with a little more bang.
The Arquebus uses renaissance-era bullets. A stack of ten costs 3 gp and weighs 2 lb.