'Flash in the Pan'

The term 'flash in the pan' usually means something that is all show with no substance . The phrase originates from the use of flintlock muskets and other flint and gunpowder fired weapons , the musket was loaded by priming the 'pan' with some gunpowder which when struck with the Flint , on the fall of the fully cocked flintlock , the powder in the pan flashed and in turn then crept down into the breach and ignited the main powder charge sending the lead ball up the barrel, if the powder in the pan failed to transfer the ignition to the main charge it wouldn't fire the gun and hence was simply a 'flash in the pan' - allied to this is the phrase ' to go off half cocked' which led to a similarly poor result and still means the same to this day .