Faststeel 12 ga. 2-3/4" , 1-1/16 oz, 1550 fps, #1shot if you can find them, #2 or BB if you can't find the #1's. I've shot several cases of them, the geese do not like this load! I find the #1's to be a perfect compromise for size vs. pattern in my guns, shooting mostly lesser Canadas and snows, but some greater Canadas too. If only shooting greaters ( 9 lb plus birds) I would consider BB's or BBB, but pattern quality suffers in my experience, but your barrels might pattern different.
Kent Fassteel was the first company to load really fast shells >1500 fps, Remington, Win, and Federal are only now "catching up" - but I mostly stick with FS because they work very well and are a good value. I use about 0.0020" of choke ( modified ) when shooting these loads over decoys, they are deadly to about 45 yards, dropping off quickly after that.