No cries of hysteria. I've had personal experience with exactly this type of thing. I was given an old rifle when I was 16 years old, by a neighbor. He had run over the barrel backing up once, and bent it. He was an old guy and didn't think anything of cutting it off right in front of the forestock, and right behind the pistol grip. It was just an old bolt action SS .22.
Anyway, I removed the bolt, tossed it on the floorboard in the rear seat area, and took it over to show a friend.
I got pulled over on the way, and the officer seeing it asked if he could handle it. I said sure and opened the door for him to get it. He looked at it, asked me if I knew where the police dept was, and said he'd follow me down there(this was 1959-60). Once there, they impounded my car, called the feds, and started questioning me as to why I made a sawed off rifle.
In the end, the only thing that got me released without felony(or any other) charges filed, or it being turned over to the feds was my brother was a cop on that dept.
They did keep my car though, and let me go into my brothers custody for a ride home.
They did call later telling me they didn't want the pos car, and to come and get it, then they gave me a ticket for smog pollution, remember this was 1959-60.
I was lucky. Do you want the thread starter to get worse treatment? The cops are way less lenient now, than then, and there are tougher federal laws.