Hey, I've got a Kahr P40 and an Mk9.
The .40 is the first handgun I've ever owned. It said in the manual to only field strip the gun for regular cleaning, and leave the rest for the gunsmiths. Well, at a training course I took out of town the gun stopped shooting. I said to hell with the manual and took it down to the little pieces.
Come to find out, there was quite the buildup of what looked like brass shavings inside the tunnel where the striker travels, and stuck to the striker itself. All that metal fouling was preventing the striker from coming into contact with the primer of the cartridge in the chamber.
I can see now that the open design of that part of the pistol will allow metal shavings and other grit into where the striker resides, causing a possible failure. Sure, it took nearly 2000 rounds for it to happen to me, but the message was clear: break it down all the way every time.
I took apart the mk9 which has more like 800 rounds through it now, and found only minimal contamination in that area, so I realize if you do this only every 500 rounds or so you are probably okay. But I don't want to take the chance that somehow during that last 200 rounds at the range, something snuck in there that will prevent it from running properly in a SD situation when my life depends on it.
From the other Kahr owners, have you noticed the same kind of problem? Do you break yours down all the way frequendly for cleaning? What about the other guns like Glocks? I know of Glocks that run for thousands of rounds without even a cleaning that work just fine. Are they designed differently to prevent this?