I think if you engage a sniper and hit him with a headshot, regardless of what weapon type it is, it should de-scope the player and if you follow up with another headshot, then they will still remain de-scoped, so basically that's the risk they take, its either get the first shot away or the weapon can be made redundant in that one to one engagement. This way I believe you will see a lot less sniping and a lot of players having to use there primary more.