Seems like you're found an easter egg. Hope they will add galil in future. It's not that common in conflict which game based in, because of high prices for this gun, so insurgents likely won't use them, but in past galil had some influence.
It's a known "bug" or "easter egg", whatever that is.
Devs said it didn't mean they were going to make Galil a thing. Maybe they will, maybe they won't. No one can tell for sure atm.
Oh ok thank you guys