I hunt ruffed grouse a couple weekends a year, one of the most challenging birds to hunt with a shotgun IF you don't ground swat or tree swat them.
The population in Ohio has declined dramatically over the past 30 years that I have chased them. I usually take trips to the northern states.
Our Wisconsin trip last weekend, I think we ran across 12 birds per day at most, plus several woodcock. Leaves were still thick on the trees, so shots were tough on flushes.
Fortunately we had an older Lab with us, the birds sat tight and with the closer ranging and slower pacing dog, had better shot opportunities. We mostly see gray phase birds. Southern Ohio birds seem to be the rufous phase mostly, which I think is a prettier bird. They both taste mighty good breasted out and pan fried in butter, salt and tarragon!
I usually use my Beretta 390 20 gauge semi-auto with warm 7/8 oz. loads of 6 shot, I/C choke. Seems to be a pretty good combo.