I've mostly relied on it shooting someone else. Take cover if he's shooting you (Which is good advice for anyone), or use a shield if you are a Bro. He seems to fixate on people whenever he shoots, so as soon as he has a target he wont change targets until you piss him off enough or they die. Doing the front thing can actually be harder sometimes because of this, since he'll ignore you if you are attacking on the back and carry on murdering your teammates. But really, abusing cover is about the best advice I can give to anyone who finds themselves against the Ranged warrior. As of weapon, I don't know. I've only used the swords, mostly because it was the only thing I had available while I farmed the achievements. They kill Gants in 3 FA's, or 1 FA + 1 CA. I don't know how the heavier weapons fare in PvE. The one thing that I find almost mandatory is to equip the lifesteal mod. It really mages a huge difference.