Hahah...I've never noticed that.
That goes to show how often I pay any attention to this mysterious "Gun AP" stat. I would believe that it was not intentionally meant to work that way, but I can't possibly know for sure though. Hopefully not.
I take it you're not a gunner? :3 well it MIGHT work to a player's advantage. You could temper the gun AP stat in game with gold tempering gems as well to get the amount of gun AP you want and you won't have to care about the AC or Lk since you would be able to temper it through web without the gun AP being touched. No one hate me for this if you do this lol