Arrow Revolver

A small, cylindrical object with six chambers bored into it. This object can be fitted onto (and removed from) any bow or crossbow, and acts as a revolver for the weapon's ammunition. As an action, you can load the revolver with up to six pieces of ammunition. Whenever you make an attack with a weapon fitted with this revolver, you can make a second attack with the same weapon immediately after, as long as there is still enough ammunition in the revolver to do so. These additional attacks do not count against the normal number of attacks you can make per turn.