Upland bird choke

[Tater]

Ok, I've hunted upland game birds before but this is the first time I'm hunting with a shotgun with removable chokes so, what is a good choke for grouse? We're going for "forest" grouse which includes blue, ruffed and another one I can't remember but I can't imagine they will be much different. My other shotgun is, I think, a cylinder bore but as long as I can change out the choke I'd like to make sure I'm giving myself the best chance to knock a bird down and make sure it stays down. Meaning, when he drops he's dead and not flopping around all over the place. So, what's the best choke? Thank you.