Can it fire other SCPs, including itself?
Well, it can't fire itself, as it would cause a paradox, because it actually pulls the objects it fires from somewhere on the planet. Also, the gun appears to work on a basis of the object being teleported into the barrel, being propelled by unknown means, and if it have to be shrunk to fit, growing back to full mass and size afterwards.
It's also selectable.
Hang on, I'm writing an experiment log
Inputted Ammunition Type: SCP-682
Effect when fired: SCP-682 hit the wall with a sickening thud, and was slightly disoriented before getting up and killing all personelle in sight.
Note: WHO IN THE forget AUTHORIZED THIS. -O5-██Inputted Ammunition Type: Nuclear Warhead
Effect when fired: SCP-████-J managed to fire a full-sized nuclear warhead at ████ KM/H (████ M/H) and destroyed the bomb range cleared for testing.
Note: Come on people, stop that. -O5-██Inputted Ammunition Type: Teddy Bears
Effect when fired: Fired teddy bears at █████ KM/H, testing upon D-Class proved this speed to be lethal.
Note: It would appear that the gun will accelerate objects that aren't deadly enough to speeds that would kill any normal human being. More research into this is required. -Researcher A███ █████Inputted Ammunition Type: DVD of the game "███████ █" by "B███████ S████████"
Effect when fired: DVDs clocked at ████ KM/H (████ M/H) Lodged inside wall, able to decapitate normal human beings.
Etc.
Poll