Suppose I had an 18 in barrel that accepted choke tubes on my 12 guage and wanted to duck hunt with it. Would that be a bad idea and if not, what choke would you use? I realize that this would limit range somewhat. Does anyone have data on the differences in pattern, velocity and drop between different barrel lengths using different ammo? I'm not really a shotgun person but I've had fun the few times I've duck hunted and I'm mostly just curious about this.