Ah, the old 'Glock unsupported chamber' myth rears its ugly head again. Lookee this. What do you see?
I see a photograph that, conveniently, puts the deeper slash under the Glock chamber in relative darkness to hide it.
How about some firsthand KB pics?
I was the person holding the Glock when this happened. The guy I was shooting with had the same thing happen to him a few days later.
These pics were from a rental chambered in .357 Sig. My friend's was chambered in .40 S&W. Both happened in guns using factory jacketed ammo. Both guns were clean, his because I saw him clean it and my rental because
I cleaned it just prior to shooting.
I have neither experienced, nor heard of a first-hand account, of a 9mm KB in a Glock.