"I've had barrels choked one way and pattern another. Choke numbers are a guide but no substitute for a lot of pattern board work."

Bingo. Choke designations are just figures. For every different shell manufacture will all shoot different.

Always get a chuckle when someone posts on here that they bought a gun that is choked such and such, have not even received it and want to know who can open the chokes.

David