Peacekeeper

Weapon (any firearm), uncommon
  There’s always been rumours in the Bureau of a celestial wing specialising in extraplanar affairs. Whether the peacekeeper is standard fare for this secretive, offthe-books department, or is simply a confiscated firearm from an over-zealous group of deva is unknown. However, with its radiant bolas, this deadly firearm is equally capable of non-lethal solutions.
  You have a +1 bonus to attack and damage rolls made with this magic weapon.
  Radiant Bolas. As an action, you can charge the firearm’s alternate firing mode, causing bright light to leak through the weapon’s joints, and fire a magical bolas at a creature within 60 feet of you. The creature must succeed on a DC 13 Dexterity saving throw or be knocked prone and restrained by the bolas. A Huge or larger creature automatically succeeds on this saving throw. A creature restrained by this bolas can use its action to make a DC 13 Intelligence (Arcana) check, dispelling the bolas and ending the restrained condition on a success. Each time a creature fails this check, the bolas tightens, dealing 1d8 radiant damage to the restrained creature.
  After you activate this property, roll a d6. On a 1 or 2, you can’t activate it again until the following dawn.
  Radiant Reload. The peacekeeper contains a radiant inductor capable of compressing energy into matter. If a cantrip that deals radiant damage is cast on the peacekeeper, the weapon creates a number of pieces of ammunition equal to half the damage dealt (rounded down), loaded into its relevant chambers. The weapon can’t hold more ammunition than it has capacity for, or be broken by radiant damage.