Okay, it's official. You have NO IDEA what you are talking about. Reasonable suspicion isn't some vague concept. You must articulate the specific crime you suspect to be in progress when the police originally approached him and tried to take his rifle.
Hint: there wasn't one.
The response from the government agent was: "Once I find out there is no issue".
So even the government agent admitted the had no, "Reasonable suspicion" about any crime.
I can’t argue with you. You have no sense of reality.