When checking in, can the pistol and ammo be in the same bag/box?

I always carry loaded magazines in my range bag, just can't have the magazine in the gun, and nothing in the chamber, with the action open. If that's not correct, then they have been letting me slide (no pun intended).

The gun cannot be loaded. No ammo in magazines. Action should be open.

Unloaded and open for inspection.

Nope