Oh yeah I remember that now sorry. You could be right his hand was in the right position but if I remember correctly he did some hand seals before and I don't think Kirin requires any, plus I think he would have needed to have Chidori in this hand first.I can't remember the Manga chapter or episode, but if you have watched all of the episodes, then its the one where sasuke beats Naruto, Sai, Yamato and Sakura, when they first met back in one of Orochimaru's Hideouts. Then he was gonna finish him off which what looks like kirin. (alot of people thinks thinks it was kirin too) But Orochimaru grabs his hand and stops him, and then they leave.
I'm pretty sure it was kirin.