No doubt many can't hit 6 of 8 crossing clays at 30 yards. To hit at that range consistently, you have to continuously practice at shooting at the distance or longer. Note to self: It's been a while since you've practice 30 yard crossers.
Cooperative North American Shotgunning Education Program (CONSEP) and Tom Roster are familar names to most USA waterfowlers. And from what I can tell it looks as if other countries are using the CONSEP charts for shooting waterfowl with steel shot. That chart is an excellent guide.
Reading some of the articles on the BASC site, it looks as if research is showing that half and three-quarter choking are the tightest that should be used, depending on shot size. Since you do mostly pass shooting half and three-quarter would be the most logical. But that somewhat goes agains what the London houses have been saying and selling to their USA customers as read in the sporting magazines. My experience with quarter/half and improved-cylinder/half chokings is that they are better than half/three-quarter when rough shooting.
