This ignition system employs the use of a hammer, a hollow bolt or vent leading to the chamber, and a fulminating mixture as a primer. Several types of this ignition system exist. One version used the percussion cap containing the fulminating mixture. The cap was placed over the open end of the tubular vent, known as the nipple, and when the hammer fell it crushed the mixture between the cap and the mouth of the tube. The flash of the exploding mixture then passed through the tube into the chamber, igniting the gunpowder.
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