In the movie
Die Hard 2 there is a mention of this new
super pistol that is all
ceramic, undetectable by metal detectors, and can hold
a lot of ammo.
It also was black and evil looking and not many people have seen a gun like this before. It looked more like a toy than a gun.
They called it the Glock 7.*
And this is where all the myths about the Glock came from, intentional or not, it effectively made this falsity fact to many people's minds.
In truth it was a garden variety Glock 17. It does have a polymer frame but the slide is pure steel. Many of the parts inside are also metal. It will show up in metal detectors and will most likely be a prelude to a cavity search if you try to sneak a Glock through the airport.
Assuming the entire gun was indeed ceramic and non metallic, the cartridges would still be metallic and would set off metal detectors. Cartridges are mostly lead, brass, and copper. Ok, ok, there are plastic bullets and plastic cases, but the primer will still be metallic. Besides, K9 will sniff the nitrates off of you a mile away. Gunpowder contains high levels of nitroglycerin.
What good is a gun with no ammo?
* - There is no Glock 7, it starts from Model 17 to I think 36 as of this date.