This item consists of a metal tube the length and width of a man’s forearm attached to a glassy gray orb in front of a large reinforced wooden stock. The stock has a hole on the back you can open and pour a bag of ball bearings into as an action. It can store up to three bags of ball bearings and weighs 12 pounds regardless of how many ball bearings it has stored. As an attack action you can strike the glassy orb and it will expel a number of ball bearings of your choice, up to 1000 ball bearings (1 bag worth), with a dull thud. Interestingly the ball bearings have increasing velocity proportional to the number of ball bearings expelled.
If you expel 200 or more ball bearings all creatures within a 30 foot cone must make a DC 15 Dexterity saving throw. On a failure the creature takes 1d4+1 bludgeoning damage for every 200 ball bearings expended, or half on a success. Creatures farther than 15 feet from you take no damage on a success.