I personally use duel pistol’s for going against multiple mobs. Just run in a circle and spam the auto-attack and the Unload skill and you should do fine. If you have the Caltrop’s skill use that as much as you can as well.
I also found that you can solo Bosses with this method if you use it properly and iv used this since i was lvl 5 (I’m currently lvl 25). I hope you found this extremely useful. (Remember this method dose not always work)