This gives me an idea: There might be a market for cheap-as-hell injection molded lower receivers, not really good for any sort of shooting at all, to be sold

This gives me an idea: There might be a market for cheap-as-hell injection molded lower receivers, not really good for any sort of shooting at all, to be sold to travelers so that they can be "technically" carrying a gun. It would be considered disposable so they could just crack it in two and throw it away at their destination (or perhaps have the shops that sell them also buy them back). I figure injection molded plastic would be sufficient, as plastic lowers have already been demonstrated. It would only work to and from certain states of course. There are probably problems with selling and buying them back in airports, so disposal in some states may be a problem. If you are flying Kansas<->Vermont or similar it could probably be made to work though.