Just found out for the "Weapons Collector" achievement you don't have to get all 13 weapon in one playthrough. I had played almost all the way through collecting most of them and then decided to start over again. After collecting three or four this playthrough it just popped.
Well I get up in the morning and I get my brief. I go out and stare at the world in complete disbelief. It's not righteous indignation that makes me complain. It's the fact that I always have to explain. - Van Morrison