There is a two paragraph blurb in the 'Traveller Book.' I will post a pic of that. It adds modifiers to -10 difficulty roll. I something on a Sci Fi blog at some point about being able to fire pistols in space. They should to the on the ISS...

I couldn't find the rules in T5

I assume that without some way to anchor your feet to a surface (mag or grav boots) melee combat would be almost impossible? I think would be really difficult to fire a rifle as well. You may be able to hang on to something and fire a pistol but even that would be pretty tough. Station Tour: Harmony, Tranquility, Unity,https://www.youtube.com/watch?v=tBVUTFPate0

Test