Pistol Sword (5e Equipment)
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Martial Melee Weapons
The sword pistol is a shortsword with a flintlock pistol incorporated in the hilt. It makes for an unbalanced blade, and an overweight pistol, but their combination frees up the off-hand for a shield or second blade. Sword pistols fell out of favor completely with the invention of detachable bayonets.
When you hit a creature with the blade you can use a bonus action to make an attack with the loaded flintlock against the same target. This is considered to be a melee attack.