Apparently it happens....Ed Burlew recommends you transport your ammo in a locked container, even though there is absolutely no legal requirement to do so, because people have been charged by overzealous officers for transporting unlocked ammo. I'm guessing they invoke careless storage or negligence or something or other, which of course will be defeated in court, if not dropped just before trial. In the meantime, you lose your firearms, your PAL is suspended and your lawyer sends you his bills.
Edit: I see Yogi beat me to it. I gotta learn to read forward before replying. Patience. Meh. :)