Always read the manual
I have three glock .40 pistol's I have never had any problem or malfunction with anyone of them, one has well over 1k rounds down range, but I do not shoot reloads, and in my opinion after reading the following out of my glock owners manual, you should not shoot reloaded ammo out of a glock pistol.
Before using the Glock pistols, the operating instructions and safety information is this manual must be read and understood.
No liability whatever can be accepted if inexpertly manufactured or inexpertly filled ammunition is used.
All liability whatever is excluded in the event of these instructions not being observed.
side note: anyone can reload ammo, but there are only a few experts.