It also depends on what type of shooter you are. Are you a quick shooter or do you let the birds run a little bit? My 20 gauge Ithaca is ideal for quail, but it has a full choke so I let the birds get out of ways before I shoot. I'll use a 12 gauge Model 21 for pheasant and sometimes I can get on them so fast they are still vertical. Or real close to it. So I have to let them get out a ways even though my 21 is I/C--- I/C. I've never shot a .410 or a 28 gauge. I guess I was never interested to shoot something so small. So, 1 1/8 oz 12 gauge or 7/8 oz. 20 gauge does it for me on just about anything.