So just for context, in the world my campaign is taking place, black powder weapons, warforged , and constructs exist. Only people that can get their hands on it are the wealthy or Pirates. The city that mass produces these technological marvels likes to keep a lot of it to themselves and only sells it to the highest bidder. One of my players in my group found this city and managed to find one of the most talented artificers. He commissioned her to make a nice battle axe for his sidekick and two guns for himself. What he wanted these guns to do is never run out of ammo, never needs to be reloaded, and is rapid fire. How can I make this without breaking the game? The game isn't built for rapid fire weapons and if there is a mechanic somewhere that balances this or sets rules in and out of combat, please let me know.