So I was quizzing the guys about the news back home, and they start referencing the bullet in the luggage, like everyone knows what that is. I had to ask, because I thought maybe my grasp of the English language was lapsing or something. They inform me that it used to be very common practice for Filipeno security or customs at the airports to plant a single bullet in your bag, find it, and extort money from you. They say that foreigners and mariners were particularly targeted. Their current president made a typically dramatic (and probably heartfelt) threat against people involved with this kind of corruption… and I guess its not that common any more.
Possible that your bullet came from some kind of scheme like this?