Gone through chapter 14 several times looking for the final weapon part (13/14) and still nada. Looks like my counters glitched because I'm referring to a video guide whilst I do it.
Looks like I finish with 57/58 because starting a new save file just for the sake of picking shit up isn't my idea of fun.
Gun Collector; the one that got away. After doing HXC legit it's pretty funny that this is the achievement that fucks me over.