Not many grouse here, but for hunting woodcock and quail with my flushing dog, I like to see what the right barrel does at 20 and 30 yards and the tighter choked left barrel at 30. For assessing where the barrels shoot relative to point of aim, I like to use a rest and shoot at a short enough distance that the pattern is just a few inches wide, 10-20 yards depending on choke.