Do you really think you can make generalities about a certain level of basic realism in a science fiction game with only one reference quoted from one only fire weapon description??
Do you want basic stuff from SciFi adult Fans? I can provide it to you.. Kiddo.
So, if I say an assault riffle which "needs oxygen around" it to be able to fire in space vacuum without a special case, is it ringing any bell? I guess not.
The LSAC 218 Machine Pistol, with its "oxygen free environment" specification, is an homage and a solution to Vera, Jayne Cobb's favourite assault riffle, 'cause "She needs oxygen around her to fire" in Firefly(TV series).. A cult series.
It's in the "Our Mrs Reynolds" episode, which leads to one of the coolest SciFi scene I've ever seen:
Vera, placed in an upper space suit with a helmet and sealed to Jayne's forearms with adhesive tapes, shooting four rounds through the helmet visor. SciFi in all its glory!!!
So do the Dev and us a favour, get back to your schoolwork. It's not an adult game for nothing...