Originally Posted by BruceO
You also erode the shoulder in the chamber, among other things. The only bad things are not just the possibility of a catastrophic failure although that may be sole concern of some.
Erosion is no more likely than with any other cartridge, correct or not. And the article does not refer to Glock pistols. We've repeated, over and over again, this should not be tried in any other brand pistol. I'm NOT trying to convince anyone to try anything they are not absolutely comfortable with, or that may be unsafe.
Only trying to dispel myth and rumor regarding THIS situation. The Glock doesn't know the difference, nor does it care. A .40 round won't fire (any more likely than if it were a 10mm round) if it's isn't properly chambered (either would be equally bad). Other pistols, such as those in the article, may. If the Glock does, it was already broken, or modified in such a way this should never be attempted (such as an extended striker, which is a bad mod, in almost any case).