I have no idea how damage stacks in this game, so I figure an EvE player would know better than me. My question has a little story attached to it, so bear with me.

I was in a game with my Charybdis just a few moments ago, and I seem to have pissed off one of the players. He had a prototype swarm launcher that he kept firing at me whenever he saw me. He was the only AV person I met the entire game. Whenever he hit me, he took my 2100 shields down to 800, from a single volley of swarms. My passive resistance is at 49.07%, and explosives do 80% damage to shields, so how much ridiculous damage must he have been doing to take a 1300 hit out of my shields with a weapon that does 1980 damage before modifiers?

I figure using civilian math that it would multiply, so 1980*0.4907*0.8, but that would equal 777 damage, a far cry from what he hit me with. Even if he had prof 5 and 3 damage mods, that would be 1980+(1980*.15)+(1980*.1)+(1980*.1*.87)+(1980*.1*.57) So 1980+297+198+172+112=2759, then using my resistances, 2759*.4907*.8=1083, still not enough.

Am I not stacking damage correctly? Am I not stacking resistances correctly? Both? I've just never understood the math of this game.

Tell me your high/low moduals

Are you sure that these numbers are accurate?

From 2100 to 800

These numbers seem a little round to me.

If I might, there's also the problem that explosive damage is probably more than what it written down. If you're hit directly in most games, it isn't like the splash misses you. It may be that the more of your body is inside the splash zone the more gets hurt, like TF2 does it. Of course, with Swarms going for Center of Mass and a Charybdis being pretty big, that could add up pretty fast.