Repeating Shot

Enchant simple weapon with "ammunition"
property (requires attunement). This magic
weapon grants a +1 bonus to attack and
damage rolls made with it when it's used to
make a ranged attack, and it ignores the loading
property if it has it. If the weapon lacks
ammunition, it produces its own, automatically
creating one piece of magic ammunition when
the wielder makes a ranged attack with it. The
ammunition created by the weapon vanishes
the instant after it hits or misses a target.