As was already said, open chokes are better for buckshot and if you can't take the time to pattern a gun you are going to use with buckshot, leave it at home. It take more than one buckshot to be quickly fatal on a deer, if your gun doesn't shoot a tight enough pattern you will be crippling them. You also need to pattern at various ranges to see at what point the sot pattern opens up too much to be effective and that distance will be closer than you think.