The actual internal profile and measurements of a WS-1 can vary quite a bit gun to gun. I have one with a .008 constriction followed by a flare to greater than bore size. It does indeed work very well as a skeet choke. Closest to this design in a modern production item are the Beretta Mobil and Optima skeet chokes.

Winchester claimed the WS-1 was designed for optimum at 20 yards, the WS-2 for optimum at 30 yards. Most would consider the WS-2 to be light modified, if not actually modified.

"The price of good shotgunnery is constant practice" - Fred Kimble