Agree with Jones. I have measured many WS1 and WS2 chokes in 12, 16, and 20 ga. Oddly, 12 ga WS1 is often as tight as .008 or .009 before flare section. You will encounter the odd unaltered WS2 12 that is as loose as .010 (though many run around .014). A further curiosity is that 12 ga Win mod can be as loose as .008. Go figure.
In 20s WS1 usually runs .003 (constriction before flare), and most WS2s I've seen were around .010. I have an unaltered M12 mod barrel that runs .007.
The two 16 ga WS1s I've measured were .003 and .004 before flare. A friend has a WS2 M-12 16, but I haven't had a chance to measure it.
I would add that if that flare section actually did something to patterns in the pre-shotcup era, it certainly does nothing now with modern ammo. On paper, WS1 patterns in accordance with the measured constriction.
Sam
