I'm sure Adrian will show you some of his patterns...he has some phenomenal patterns, regardless of how big the gun is. You'll see when he posts. I've seen them before...I'd feel comfortable using it as a 60 yard gun. I won't use my 20 at 60 yards, but it doesn't pattern nearly as well as his. 60 would be the absolute limit with my 12.
Wait...did I just say that Adrian had just as good a pattern with his 20 as I do with my 12? Well, reckon that's the way it sounds.