system
Given the following post, respond as if you're commenting on Reddit:
human
Can you actually make a plastic gun? [X-men]

A common human tactic to counter Magneto's powers seems to usually involve plastic guns that shoot plastic bullets or darts. Is this possible? Would it even do any significant damage?
gpt
There are plenty of modern day polymers that are as hard as metal, so yes, a plastic gun is both possible, and can even be printed on a 3D printer. 

Non metallic rounds are a bit or of a challenge, but if the only purpose is short range non-armor defeating anti-personnel rounds, in other words, they only have to penetrate flesh and do damage, then there are lots of non-metal materials that will do just fine.