I'm relatively new to owning a Glock. I have a Gen 4 G19. I'm now comfortable completely disassembling the slide and receiver and encountered something after disassembling the slide for the first time. With the gun racked (with or without a round in the chamber), you can hear a very small amount of movement from the firing pin if you shake the gun back and forth. It's clearly nowhere near the amount of movement as when the trigger has been pulled (the firing pin safety is working), but should it be moving at all? I don't recall if I did or did not hear this prior to a full disassembly and I'm just wanting to make sure this is normal.