Tanks,Snipers

There should be no reason for to be able to run someone over with tank and they don't instantly die i have ran over countless of players and not one of them have died yet that should not be a mechanic in the game at all if this game is supposed to be on the realistic factor of any game out there. now with the sniper in the beta so far it makes absolutely no sense what so ever if i have the same attachments as the opponent and they shoot me in the chest one shot kills me i should be able to do the same there shouldn't that much of a difference i understand if i didn't have the sniper maxed out but when you take a shot towards the upper chest and a certain distance you should die no matter what