Ammo help

Going hunting for grouse and prairie chicken in September. Just wondering what size shot you guys would use for these birds and what brand ammo you prefer in 12g a.
Thanks

2 3/4 6 shot

I don't know about the chickens but the grouse 71/2 or 8 dove a quail load works fine. They cannot take near the punishment a dove or quail will. 20gauge works great.

Sage grouse that is. Thought they were way bigger than dove or quail.

Always used Winchester double AA 7.5 at 1300fps.

They are big and slow and easy killed. They do not carry off near as much lead as a dove or quail will.

September birds will be the young ones and sixes will work just fine. Huns will be part of the menu also and they're a fun bird. Don't shoot more than one of the sage grouse( mounting purposes only ), wait on a big old male bird and be selective who you let mount it. There isn't too many (Sage Grouse ) anymore and they are about the same as shooting a flying armadillo. Sharptails and Huns will be your main birds, watch early mornings along the edges of the wheat fields with a good pair of bino's, all you'll see is their heads sticking up. Dogs will work fine after the initial flush and you get them scattered.
What part of Montana? or which state are you going to hunt?
I wish I was going with you, it is a blast.
P.S. take your flyrod too.

Thanks txdogman. Actually going to Colorado North of Denver for the 2 day season. And definitely taking the trout pole!

Some things that matter. It's North Park, so Sage Grouse is only a 2 day season. 2 per day. Possession limit also 2. Half the area we will be hunting will require non tox shot. Up to 7 pound birds. If the decision is not postponed, this very likely will be the last open season for them in our lifetime if not forever. Bonus birds nearby that will be hunted Snipe, Rail, and Dove and they will require non tox do to location. Blue grouse areas lead ok. Long drive to the sharptail areas and Ptarmigan areas, but possible. One of the sharptail areas is non tox as well. All Snipe in Kansas are Non tox. Combined with Teal anyway. Canadas possible and i will have what is needed to bring them to us if so. I think all the Prairie chicken areas we hit will all allow lead. .

Do you like steel best or do you use something like hevi shot?

For a two bird limit with a two day season that will be the last or next to last season ever and driving 100s of miles to get there. I'm using Tungsten Matrix. Probably #5, but could be #4 or #6. Shoots like lead. Then #7 steel for the small birds. I like the wad design Fiocchi uses with their 7 steel to use in my fixed choke barrels, but your on your own there. Every shotgun is different. Consider too we will be above 8000 ft elevation. Air is less dense. Patterns could be tighter and may even give a few more feet of effective range.