Both first-hand experiences were with other people holding the gun, and me holding the timer in practical competition. Both guns were Glocks, both had the mag and extractor blown out, but both guns were returned to service eventually, one needing a new frame.
For a week after the first incident, I had thoughts of a G20 extractor embedded in my forehead.
Pachmayr brand rubber grips were widely recommended for those experimenting with heavy handloads, because they are rubber over a sheetmetal panel, thought to give a little extra protection in case of a failure.