Choke for heavy-shot?
 

Any feedback on chokes for heavy-shot would be appreciated, I have a after market choke (pittman) for my 835 with a holo-sight scope and have been using winchester 3-1/2, #4 high velocity magnum have them pattern good and have dropped gobblers over 50yards. Why change you ask? Well the model T was good but glad they changed that-lol...... if the heavy-shot has greater impact great but it is not shooting near as tight with my present equiptment and I figure it must be the choke and There are several new chokes just for Heavy-Shot so without buying them all I'm lookin here for advice as to which I may get the best results with....thanx