DWM,
Regarding "supported" versus "unsupported" chambers:
This is one of those "shades of gray" situations. To the best of my knowledge, ALL semi-auto pistols use chambers that are cut away some at the bottom to ease feeding. Some are opened just a bit, some leave a third or so of the brass exposed, and most lie somewhere in between.
If you look at a cross-section of a pistol cartridge case, you'll see that the area just forward of the extractor groove, known as the "web", consists of brass that's much thicker than the case walls that run the rest of the way down to the mouth. Having this portion of the case unsupported is no big deal because the thick brass doesn't need reinforcement. Problems arise when the area further up is exposed, leaving only a thin wall of brass to contain the pressure. The more case wall that's exposed, the higher the risk of a blow-out (or kaBoom!).
Another factor to look at is the overall tightness of the chamber. The tighter the chamber, the harder it is to feed a cartridge into it, but the looser the chamber, the more the brass will stretch (and weaken) upon firing. Glocks tend to have loose chambers; I can drop a round into my G23's chamber (with the barrel removed from the pistol) and rattle it around. The combination of that looseness with a large feed ramp cut-out is what makes Glocks susceptible to kaBooms.
I don't think that's a problem with Kahrs. In fact, the problems that I've read about have stemmed from chambers that are so tight that most reloaded ammo won't fit in them.
If you're worried, the quick way to check is to look at the empty case of a round that was fired in your pistol. Is there any bulging near the base? If you can't see or feel any, you're OK. The more refined way is to check case expansion with a set of calipers, but that requires a knowledge of just how much expansion is acceptable and I can't quote you any figures.
