Forum:Double consumables - undead nightmare

I've completed all of the ambient challenges in Undead Nightmare (Legend of the Apocalypse outfit unlocked) and have noticed that all my consumables are double capacity (including double capacity ammo on all weapons). Is this a result of completing rank 5 Undead Treasure Hunter, as it is in RDR? Or is it unlocked because of something else? Really don't want to start the game again and find out....not at this stage anyway.....lol.