Gunslinger VS Bluebird, nexon screw up?

gunslingers cant use almost any weapon from the CS. however, the BLUEBIRD, does NOT say "except guns or knucklers" it just says any weapon. why would that one be the only one? can anyone confirm that it actually works with guns or did nexon just forget to change that ones text.
(and why dont guns preview fire in the CS? bows can...)