User blog comment:A Lonely Nomad/Is this meant to be right?/@comment-1921109-20100702071647

Well, what is defined as "hard" is subjective, but I think the idea is that the easiest guns are unlocked first, so as to get the feel for that weapon type. The "powerful" guns like the Glock 18 and the AA-12 are unlocked early on so as to give new players an advantage against the more experienced players.

Point of post: The "hard" guns are generally unlocked last because they are meant to be effective only in the hands of a skilled and experienced player. How true this is I don't know, its just a theory.