How do I get custom weapons on the stock maps of bo3?

Game Modding | Call of Duty: Black Ops 3 | Models & Animation

Cosmo Wishbone:

I know that I have to edit the .csv file in game data folder, but that didn’t do the trick. I’m assuming I have to add the weapons into the zone files of the stock maps but I don’t know how to do that. Any help would be greatly appreciated.