Seems like the loaded part would conflict with the transport part- especially if he is not going to range. IF you are going to use a key to get to your gun, why not take the time to load a mag.

Under what circumstances could a cop ask to see in a locked case? I assume curiosity would not be appropriate PC?

I've asked the question about rifles/SBRs which are not allowed as CCW weapons in CO. Carrying them in a bag unloaded seems to be a no-no because the transportation authority implies you are going directly somewhere specific to use it. That was the non-lawyer consensus.