My late mother kept a loaded Beretta 418 (6.35 cal) next to her bed for many many years. When she passed away I retrieved the gun to find it was impossible to for me to pull the slide and eject the round. My son helped me disengage the extractor and open the slide. Then with a small screw driver used as a lever and lots of WD40, I removed the round. I never thought of taking it outside and firing it; so, I don’t know if it would have ejected the casing.