You can experiment using various sizes of lightly crumpled up newspaper and once inserted past the bore, it can be tamped down and packed over the powder and can provide a type of cushioning wad without having to remove the choke.
I've also tried combinations of triple sized cotton balls with newspaper too, but I guess trying this may depend on whether you are shooting shot loads or not and how much space you want to risk having over the powder.
I then used smaller amounts of more lightly tamped newspaper or cotton over the shot load. Cotton can smolder a little bit though.