This is DUMMY AMMO and is UNABLE to fire any projectile, or be modified to fire any projectile.
Reproduction Ammo Boxes and Replica Dummy Ammo - Marshall's Arsenal
9mm Dummy Rounds. 25 Rounds - The Perfect Shot
9mm Dummy
Luger Prop FOR SALE! - PicClick
Replica Airguns Blog Airsoft, Pellet, & BB Gun Reviews
Stick them with the pointy end” – A brief introduction to ammo for props managers – random ranting
Luger Prop FOR SALE! - PicClick
Guns Do Not Work That Way - TV Tropes
Luger Prop FOR SALE! - PicClick
How to recognize blank bullets - Quora