Not.
For LE, they always assume everyone is armed anyway. I'm fairly sure they don't give a ***** about how someone acquired a weapon, they're more concerned that a person might use said weapon on them.
Make all the "undetectable" guns you want...the ammo still isn't. I understand the fear that the left tries to portray and push to support the law but it's stupid stacked on stupid. And the result is useless.
Yes. Guns are suppose to be made of at least 3.7 oz of metal and if everyone is thoroughly checked through security check-ins anyway, then this should not be a big ordeal.
There's no such thing, so I'm leaning toward a 'not'. History repeats itself again. The same nonexistent plastic pistol scare made the rounds when Glocks first came on the market. If it weren't for the money we waste on useless laws, the panicky anti-gunners would be good entertainment sometimes.
Let's see: $3000-$5000 for 3D printer. Quality of plastic unknown. How many rounds fired until it blows up in your hand?
It'd be safer to make a zip gun for a few bucks!
Either will land you in jail.