So if I were traveling in PA with my valid AZ carry permit, which is also valid in PA, and carrying my old five year old LCP, that I bought from a guy who bought it from a guy, etc. as a backup gun and I had an interaction with law enforcement they could confiscate my weapon?
I’ve had a Bucks permit for 20 plus years and have never EVER heard of a cop confiscating a gun not bought in PA. Either you have a permit or you don’t. I’ve been stopped for traffic violations while carrying, carrying a pistol I’d bought out of state and there were no issues whatsoever. The cop never asked where I’d gotten the gun.
If the cop is suspicious of the gun, they can run a national database check to see if the gun is reported stolen. If it isn’t, they have zero probable cause to take it and would be slapped with a lawsuit if they did. This sounds like an old wives tale to me. If it’s not, I’d invite the OP to provide a source