how are you playing zero. are you sniper class melee class or short range weapon class. as for sniper class you want to to get sniper skill all way down first the work on last part tree. you do not have to fill whole sniper skill up. since all you want is last skill from that tree. then you work on your bloodshed next then go back to sniper skill. also your going to have to find good sniper rifle with high damage. you also going to want good rifle with highly effective vs armor too. i carry none elemental rifle, highly effective vs armor and highly effective vs flesh guns since that best 3 types you need. once you hit lv 50 only need carry none elemental rifle and highly effective vs armor. since your head shots will done tons damage. as for highly effective vs armor better then vs flesh or other guns since damage same but they take green damage any way. also frees up backpack space.