https://us.glock.com/customer-service/faq
Can I dry fire my Glock pistol?
It is ok to dry fire your Glock pistol, but in situations where the pistol will be subjected to continuous sessions of dry firing, the use of a snap cap or dummy round is recommended.
There are other guns that dry firing could potentially cause damage to; Glocks are not one of them. I have dry fired thousands upon thousands of times through my Glocks with no issues.
I've heard that, too. Seems like the old man explained to me why one time but all I heard was "blahblahblah" ... haha! I'll ask him again tonight why that is and post. Unless somebody else beats me to it. All of our rimfires are fairly new guns ... or conversion kits (one of those is a Glock). He said not to dry fire any of them when the conversion kits were in them.