The P99 has a lot better supported chamber than my Glock does. I've noticed in shooting .40's for some 10 years now, that they do tend to swell, no matter what gun they are shot in. They swell a little more in Glock's. I've gotten to the point where I only shoot .40 brass about three times and then toss it, no matter what weapon I've shot it in. The brass will start deforming too much after that, for me to be comfortable in loading it again. Luckily I've never had a kB!, but I think it's because I inspect my cases, especially .40's, fairly well.