So I measured a 682X frame and infront of the hinge pins my calipers showed 1.574" where as a 686 frame 1.541".
The 682X frame width at the hinge pin was .183" compared to .165" for the 686 field gun.
Anyway, I have a couple of 680 series forearms.
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First one is a field, the other three are the Beavertail Trap style.
They all measured 1.60" in the area where they contact the forearm metal.
The last one had the factory finish stripped.
Here are a few more pictures, let me know if you'd be interested in any of these.
Thanks
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