The sure fire way to get Exotics is through Exotic bounties.
English
-
It's a shame none of them are the weapons I want though.. I want to decrypt mine like everyone else.
-
Keep farming man, I've only decrypted one exotic from a legendary. And I've probably put in about the same amount as time as you. Just keep grinding and it will eventually come. Who knows it might even be the exact piece you want!