Lesson learned: When you don’t know what resists you’re up against – bring a LOT of ammo.
I went to Agrallarier last night and scanned down three mission runners. The first one, however, was all it took to make my night interesting. He was in a hyperion, and shot at me pretty soon after I stole from him.
I returned in a rifter, and started shooting him. His shield wasn’t going; or really was going down very slow. I kept switching ammo types in both the projectiles and in the rocket launcher.
I was able to gather a 1 Million ISK bounty out of him. I asked for 10, he gave me 1. I kept shooting.
Eventually, another non-allied (though possibly friendly) person showed up. He shot up the ship enough to get the mission runner to eject and then stole the hyperion. If I could have flown it, I would have done the same, leaving my rifter there in space.