The aimed shot actually did 150,000, if you count the bleed effect from piercing shots.
When I have these buffs, my chimera shots do 91,000 (Including piercing shots)
I can shoot them both at once, due to the global being reset during the cast.
So, I give you: The highest damage in a Global in wow, 241,000. You will just never see it because no one has 241,000 hp >.>
Short demonstration on how to kill a mage.
Please note, this was done on a live server, versus a resilience-less mage reroll. (Don't we all love killing those?)
In case you are wondering how the damage was that high, look at the buffs. This is not possible in a duel, rated bg, or arena.