Free: Contests & Raffles.
I'd go with 6's but 7 1/2's would be ok too.
I've settled on #6 shot for my Franchi O/U with modified choke for the first shot and full for the second. You don't want to go too tight on the choke for a close in shot or you won't have much bird left for the grille. Makes for an interesting "feather cloud" though....If you are thinking about going for the big blues in the high country, you may even go to a #5 shot. They are some big birds.Save the #9 for quail.
Has anyone ever tried a sling shot for this?
You think that since it might be way harder to do that it would be a legal method of hunting them.
Head shoot them always. #6 shot size.
The 28 gauge seems like it would be the perfect grouse gun. I may have to get one someday.
6's and 4's would be my choice.
Grouse are not hard birds to bring down. a 1 oz load of 6's or 7.5's is plenty, as long as you do your part. If all I had was a full choke 20, I would give polywad a call and buy a box of spreader loads, to turn your full choke into a modified. If you do manage to connect at close range with a full choke, that is not a bird I'd want to eat. Open up that pattern: you'll kill a lot more birds.