Stevie - I'm really not sure you would be able to get a 'tight' pattern at 35-40 yds no matter what wad/shot cup combination you used from a cylinder bore. About the only thing you can do is increase your quantity of shot to provide a denser pattern. If it were me, I would stick with a 1 1/4 to 1 1/2 oz load of 5 or 6 shot and try to get your bird inside of 25 yds.
But you never know, I could be wrong. Its been known to happen once or twice before.