Don’t have a lighter, but have a round of 5.56mm in your pocket? Your’re in luck because that’s all you need to start a fire—and it doesn’t involve shooting that round!
As the video demonstrates, you can start a fire or light a firework with a single unfired round of centerfire ammunition. First, pull the bullet and dump the powder out. Then strike the primer on a hard surface and the residual powder and primer are enough to light whatever flammable materiel is in the cartridge neck.
This trick could come in handy in a survival situation, or if you just want to show off your fire-starting skills. As always, practice caution when handling live rounds because there might be more powder than you expect left in the case.