Use a choke recommended for hevi shot. If it says lead only then you can use lead only. Believe it or not Cabela's makes a very good hevi shot choke for a cheap price. Get it in Super Full or the tighest constriction possible and you'll be amazed and what the the 835 and the choke can do with Hevi Shot. I have an 835 and this is the setup i used last year. Good luck come spring!