Kahr customer service has not answered my question of what the spec is.
I think I am just stuck with figuring it out for myself. I measured three of my Kahr's at .032" and one is .028" so my guess is spec is .032" with a tolerance of +_ .004" or if less my .028 is out of spec.
I have seen on other threads that they will suggest a user try different brands of ammo if they get light strikes. I think that is unacceptable as I think a firearm should function with all brands of ammo that are in SAAMI specs.
The extractor will hold the round tight to the breech face so even a loose chamber or short case should fire 100% of the time which is required of a firearm.
I think there is a SAAMI spec for protrusion as it becomes part of the chamber but I can't find it. It is obvious to me that every manufacturer has a spec but Kahr is just not sharing theirs for some unknown reason?