Iron Bundle's best moveset in Pokémon GO is Splash and Struggle, with 13.04 damage per second, and it can deal 333.3 damage before Iron Bundle faints. This is true when battling in neutral weather.
All Iron Bundle movesets ranked
Here is a complete list of Iron Bundle movesets in Pokémon GO, ranked by their DPS and TDO. You can change the weather and the opposing Pokémon.