Just a possibility but, does the chuck have a setscrew to limit the amount of expansion.
My first chuck was Woodcraft and it doesn’t. I also noticed the expansion range on yours is about 1-3/8” compared to my Novas of about 3/4”. My guess is, with larger jaws in particular and using expansion, as you retighten the jaws you can expand them to the point where there is almost nothing holding them on. I expanded my Woodcraft too much several times and the jaws just fall off (that chuck is now fitted with pin jaws only). My second concern would be that in expansion the jaws may extend quite a way beyond the chuck body and the holding point is cantilevered out from the chuck body.
That said, if you cut the minimum opening for the recess, you should only need to expand them maybe 1/8" for maximum holding power.
By minimum I am referring to the closed diameter, just enough for the jaws to slip in. Given a dovetail you should reach the maximum holding position as they expand into the dovetail. I cut the minimum diameter for all of my jaws when using expansion.
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