You shouldn't expect anything aslong as you don't got atleast 600 resi or so.

My suggestion is to get full stormhide at lvl 78 and do AV. you just need time played to get used to the 5 shamans, with full stormhide you got a good chunck of hp and 300ish resi. I did this quadboxing 4 shaman and got Wrecking ball( 20 Killing blows without a death) and Damage Control (300k dmg done to players) in the same AV, as an example. This is much more enjoyable (easier) then lvl 80 pvp, because people are leveling, they're here for exp and fun. Besides that most people run around with 0 resi, so they die like flies. 4 x magma + fire nova on every CD and TS to finish it off is great aoe damage on melee.

At 80 a well played pvper in full relentless using everything he can to annoy you can be extremely frustrating.