Funnily enough I have completed the game to 99.29%. Have got all the collectables but I seem to be stuck on 10/13 attachments too.
I haven't noticed them being collected or awarded at all, they just seem to appear on the campaign overview pane.
I seem to find that on a replay mission, if I were to pick up a eg. Scarab, I can't ping the silencer onto it but I will be able to on a different mission.
Upshot is - I have no clue which gat is mising the attachment.
So what do you do? Kill a bunch of people and hope it's with the weapon you don't have a particualr attachment for and hope you get it?
Any help would be much appreceiated
