there are a lot of urban myths and often things are poopooed by people who couldnt get it to work or have read bitter accounts by others which can be as guilty as faulty manuals. like the bullet trick mentioned. the manuals also say that you need to make sure the bang doesnt blow the tinder ball away and to cover the ball with your hand or boot. the principle of using the flash to light a fire is a sound one. anyone on the IBSR ranges who has inadvertantly set the grass alight during a pepper pot will agree with me as i've done it and seen it done several times. peat fires on the ranges are also common and not just from the use of tracer rounds. tying a loose grass ball around the muzzle and firing into the ground would probably work as well and i've not read that in a manual
same with the solar still, the physics are sound as anyone in a sweaty tent or poly bivvy bag will agree with, the variables are down to whether the ground has enough moisture to trap in the first place. if it doesnt then you either have to supply the water yourself or change to a dew trap.
sometimes though these things are like fishing kits - they are proactive in getting you to do something instead of lying there feeling sorry for yourself.
same with the solar still, the physics are sound as anyone in a sweaty tent or poly bivvy bag will agree with, the variables are down to whether the ground has enough moisture to trap in the first place. if it doesnt then you either have to supply the water yourself or change to a dew trap.
sometimes though these things are like fishing kits - they are proactive in getting you to do something instead of lying there feeling sorry for yourself.