I purchased a brand new Grendel P-10 in 1988 (give or take a year), and about the 3rd time I took it shooting, I accidentally dry fired it when the slide failed to lock back after the last round. There was a "click", and when I opened the action, about a half inch of firing pin fell out of the gun. It had a hollow, light weight firing pin. I returned it to the factory with an explanation, they fixed it and returned it with a note chastising me for having dry fired it, explaining that because of its design, it should NEVER be dry fired.

Also, my Father came back from WWII with an Astra .25 ACP pistol (along with a P-38 and a Radom.) At some point after the war, the firing pin broke. I can't say for sure what its history had been, or what the cause of the broken firing pin might have been.

Tim