I had a similar issue. I picked up the schematic on my 'lock and started gathering the mats. Before finishing picking up the mats I showed a friend where to pick up the schematic and I unwittingly picked up a second set of schematics. I finished gathering mats, picked up the quest to get the firing pin and set off to take out the captain. I was able to kill him and everything all the way through the ketch, listened to my ghosts sappy story but never was rewarded with the rifle. I now have a bare set of schematics sitting in my inventory that it appears I now will have to discard and start the whole quest line over again. Because taking out the captain was just a walk in the park... Any chance this can be fixed so I don't have to rinse and repeat? UPDATE: So I tried to see if I could pick up the quest line again with the schematics I had in inventory but I couldn't. So I discarded it and went to pick up another set of schematics. Seems you can only pick it up once on your own so I'm guessing I'll have to find someone who hasn't pick up the schematics yet and have them open the gate and run back to pick up a new set of schematics and go through everything again. Of course that's all predicated on the assumption that I can even start the quest line again now that it's been completed, which I seriously doubt. I'm starting to think that the reason it didn't work for me is that when I FIRST killed the captain, he was still behind the gate and it hadn't opened yet. Once he was dead and I got near the gate he and everything else spawned in the middle of the room (even though they had been killed already and he had dropped the item which subsequently disappeared when he spawned in the middle of the room. C'mon Bungie, I did legitimately kill him and did every last thing on this quest line, I just didn't get the weapon reward. Please help.