My pistol sounds like there is something loose in it. I've put may e 50 rounds through it and it started noise. Wasn't making when I bought it new
If there's no round in the chamber and the trigger is to the rear, the firing pin free floats in the slide and rattles around. It's normal, and in fact if you don't hear it, the internals of the slide may need cleaning.
It's the firing pin moving back and forth inside the channel, this is perfectly normal, if you didn't hear this then there would be cause for concern but there is no issue here and hope you have a great time feeding your Glock more brass
