You test common weapons each week for the gunsmith. This allows you to buy weapons and get them on armsday, which is every Wednesday. After purchasing a package from the gunsmith you wait until the next Wednesday and you can go to him and he will give you your weapon from a package. Note: If you buy a package on Wednesday you have to wait another week. Every rank you get a random weapon on spot after ranking up. At rank 2 he gives a quest for a class-specific legendary weapon. Titan: Immobious, Warlock: Susanoo, and Hunter: Stillpiercer. When you hit rank 3 he gives a quest for a class-specific exotic. Titan: Fabian Strategy, Warlock, Tloac, Hunter: Ace of Spades. At rank 5 you get a quest for the First Curse exotic.