Fully loaded, ready for combat. The ship list tells you MAX weight, not standard weight or light-load weight, or any other silliness like that.
At the NATS ive been to Capital ships are often weighed dry (before getting wet during speed testing), empty co2, no bbs. If it was me I'd put an empty 12g in and weigh like that. YMMV
I always weighed mine with an empty cartridge and empty guns and heck a dead battery if I thought I was close