Good morning! welcome back to war! Back to yesterday's subject , crossing the metal detector...1. its impossible to beat magnetism poles with a metal insulator, if not seen the electron position 2 the electrons position go horizontal 3 metal that can defeat magnetism print reading like NiFe (nickel iron, or Invar) depend on the temperature 4 then we must conclude to defeat Curie temperature, than guns would be transported in cryogenic freezers.5 However, if the transportation is inside an hexagonal box (cage) with a metal insulator, the electrons poles stay confused. Conclusion, you will need a specific transport scheme box. Anyway, here's the most common faraday cage available, the door of the microwaves stoves (are you seeing the hexagons?) :