My level 55 character doesn't break a sweat on survival mode, when he is carrying his "double shot" bolt action .50 cal rifle. He's also packed with a .308 bolt action rifle which adds energy damages. He was being shot at by that drone which has 2 mini guns attached to it, and maneuvers around by 3 wheels (you know what I'm talking about?) and then with a turret on top of the building... Yeah. They didn't stand a chance. I have Cait with a custom shotgun with that "quick release drum". I have a lot of modifications in my gear
that I found in the game which I customized to make my character stronger.
However, my level 5 character on survival doesn't survive more than 15 seconds
I have to add that Cait loves her grenades...