My buddy is borrowing a Super 90 auto from a friend of ours.  We shot it today with the Xfull choke that he gave us and it didn't pattern worth a hoot.  What choke type does this gun use?  Invector?
Anyone have much experience with what constriction would work best for this gun?  Its got a 28" barrel.  I'm looking at the JH and they have a .655.  Thats got to shoot better than the spray shot we were getting today.