Main storyline mission: Kill warrior. Do not moonshot him. Die by jumping into lava. Autosave (personally I think dying is unnecessary and perhaps you can just save and quit, but I can't confirm if that works the same).
Load up the game, load a 2nd player on splitscreen. Player 1 (your main character) does nothing. Player 2 (doesn't matter if its a new character that is level 1) goes off and activates the moonshot. Collect loot (high chance that one of five* oranges will drop, idk, something like 50%+ chance). Go into badass menu, disable, then re-enable badass stats. It saves ONLY on player 2. Player 1 signs out, game is reset. Sign back in on player 1 and repeat.
* there is a very small percent chance you will also get some other oranges, but don't bet on it too much.
Anyway, I got about 20 or so oranges, mainly variants of the CC, Flakker, Volcano, and lots of Impalers. I got just 2 Leeches, and 1 Neogenator. I got sick of all the CCs and Flakkers and finally decided to stop and save it (so I can no longer moonshot farm and move on).
Calling someone a kid on a message board = Lack of wit http://img245.imageshack.us/img245/2605/oilup.jpg