Flushing or pass-shooting?
Flushing...
Just my opinion, but the best time to hit a rooster it right when they level off, aiming right at there head!
It dose not always happen, but most of the time Roosters will flush straight up, then pump-it toward the direction there going.
That split second that they seem to level off is my best shot.
My second best shot is when there out there a ways after everyone else had there chance, and hit them with a hi-brass full of #2 or BB's from a tight choke.
To me it's not as gauge specific as it is getting over the idea that there hard to hit/kill.
