00Buck shot?

Kick's makes special tubes for buckshot, you can find more info on the net

This is something I've been researching also. I too have heard a variety of opinions on choke size for buckshot. I've been told that tight chokes are good for buckshot, but have also heard of the opposite being true and that tight chokes actually hurt your pattern with buckshot. Since I have gotten such an array of answers I decided the best thing to do would be to run some pattern tests with my shotgun. Besides, the gun, choke, and load used all make a difference and it's all about finding the right combination. I'm going to start with the factory chokes before trying any after market brands, but I'll post my results.

I've been told that Kick's will exchange chokes for you until you find the one that fits your needs.

Im concerned about blowing the end of my gun off. The guys at sportsmans told me that anything tighter than an mod will run the risk of blowing the barrel up. If I knew it was safe I would go do the same thing. Just pattern them.

It looks like it depends on the manufacturer of the shotgun. Remington's website says to use modified or improved cylinder chokes. Mossberg's site said full was okay. I don't know what the recommendations are for my Benelli Nova, and there was nothing stated in the owner's manual, so I will have to contact them to find out.