Here's an article by Bristor to give you an idea of how technical he can get about every little aspect of shooting!
http://www.briley.com/articles/game_of_seeing.html
Here's what he says about Jess Briley. BTW, I started using Stan Baker ckokes about twenty five years ago.
"Bob Brister, a Houston outdoor writer who is possibly the world’s top authority on shotguns, remembers those early days. “I have known Jess since the beginning because we both shot at the Greater Houston Gun Club,” Brister said. “We had a bar in the club and after we finished shooting, we’d all go back for a drink or a beer. I have very vivid memories of the guys giving Jess a tough time about working on these chokes. They’d kinda joke about it behind his back, and say, ‘Well, that can’t work. Those things are too thin and nobody is going to put those things in his gun.’
“Jess was already building ‘em in his garage and shooting ‘em,” he remembered. “I was one of the first ones to put ‘em in a fine guns. I had a pair of SO3 EELL Berettas that I shot pigeons with and I put ‘em in mine. Of course, there were a lot of people knockin’ the chokes. The gun industry didn’t like it, for example. There were other people making chokes. One of them was Stan Baker in Seattle. Without calling anyone by name, Stan spoke out against it. He said, ‘Thin is thin; too thin is too thin.’ Stan put chokes in guns all right, but he was expanding the barrel and then making screw-in chokes. The problem that some of those chokes had with that system was getting the chokes to shoot to the point of impact. I know because I had a set that didn’t.
“Jess figured out very quickly a way to do that,” Brister insisted. “He can get those barrels tapped for those chokes absolutely perfectly concentric to bore every time. Jess made tools for the oil patch and he reads everything. He is very much into science and he loves metals. I asked him recently if he was a master machinist. He said, ‘Well, I don’t know, but I’ve been at it for 60 years and I just love it. I would prefer to call myself a machine shop bum.’
“In those days there were very few steels used in either choke or barrel manufacturing that were really good,” Brister related, “but Jess knew a hell of a lot about high tech steels. He can tell you where they came from and their backgrounds. Some were developed for the Manhattan Project and some were developed to hold engines on World War II airplanes. Jess got into these high-quality steels … very high quality steel. He knew not only about the hardness of it, but the yield strength factor. He is, in a way, a genius at what he’s interested in. Jess can tell you a little bit about anything you want to discuss … physics, anything. He’s read up on everything and he knows pretty much what’s going on.”
http://www.briley.com/articles/one_on_one.html
One of my hunting buddies lived in the same town as Briley and used to help him test his chokes when he first started developing them. He also used to hunt ducks and quail with Bristor and he used to tell me all kinds of great stories about Bristor's shooting abilities. Bristor usually tried to get two birds with each shot and did it a lot.