8 trips. Only happened once. Unfortunately it was a trip to Cameroon. Air France misplaced the ammo box, and it didn't arrive with me. I left for the jungle the next day on a charter, but still no ammo - only one flight a day from Paris, and it arrives late in the afternoon. The ammo finally arrived, but there was no way to get it to me, short of chartering another plane, so I got it on departure day. Gift for my PH.
Fortunately, I was using a .375 H&H, and there was some ammo available from my PH. And fortunately (or not, depending on your perspective), you don't pull the trigger too often in the jungle. 14 days, 3 shots. Two on one animal.
Lesson? Unusual calibers are best left at home when you're going to Africa.