With modern reloading you can make just about any choke do what you want it to do.If you read the shell boxes you can do about the same thing with store bought shells.Like I said whats stamped on the barrel or tube is close enough for most all shooting.I'm also saying whats stamped ain't fact untill its proven and there is only one way to do that and counting pellets is the way.If you get the desired results with what you have then facts don't matter what ever they are as your hitting what you shoot at.