Matchlock

The matchlock was the first mechanism, or "lock," invented to facilitate the firing of a hand-held firearm. This design removed the need to lower by hand a lit match into the weapon's flash pan and made it possible to have both hands free to keep a firm grip on the weapon at the moment of firing, and, more importantly, to keep both eyes on the target.

The classic European matchlock gun held a burning slow match in a clamp at the end of a small curved lever known as the serpentine. Upon the pulling of a lever (or in later models a trigger) protruding from the bottom of the gun and connected to the serpentine, the clamp dropped down, lowering the smoldering match into the flash pan and igniting the priming powder. The flash from the primer travelled through the touch hole igniting the main charge of propellant in the gun barrel. On release of the lever or trigger, the spring-loaded serpentine would move in reverse to clear the pan. For obvious safety reasons the match would be removed before reloading of the gun. Both ends of the match were usually kept alight in case one end should be accidentally extinguished.

Earlier types had only an "S"-shaped serpentine pinned to the stock either behind or in front of the flash pan (the so-called "serpentine lock"), one end of which was manipulated to bring the match into the pan.

Most matchlock mechanisms mounted the serpentine forward of the flash pan. The serpentine dipped backward, toward the firer, to ignite the priming. This is the reverse of the familiar forward-dipping hammer of the flintlock and later firearms.

A later addition to the gun was the rifled barrel. This made the gun much more accurate at longer distances but did have drawbacks, the main one being that it took much longer to reload because the bullet had to be pounded down into the barrel.

A type of matchlock was developed called the snap matchlock, in which the serpentine was held in firing position by a weak spring, and released by pressing a button, pulling a trigger, or even pulling a short string passing into the mechanism. As the match was often extinguished after its relatively violent collision with the flash pan, this type fell out of favour with soldiers, but was often used in fine target weapons.

An inherent weakness of the matchlock was the necessity of keeping the match constantly lit. The match was steeped in potassium nitrate to keep the match lit for extended periods of time. Being the sole source of ignition for the powder, if the match was not lit when the gun needed to be fired, the mechanism was useless, and the weapon became little more than an expensive club. This was chiefly a problem in wet weather, when damp match cord was difficult to light and to keep burning. Another drawback was the burning match itself. At night, the match would glow in the darkness, possibly revealing the carrier's position. The distinctive smell of burning match-cord was also a giveaway of a musketeer's position (this was used as a plot device by Akira Kurosawa in his movie Seven Samurai). It was also quite dangerous when soldiers were carelessly handling large quantities of gunpowder (for example, while refilling their powder horns) with lit matches present. This was one reason why soldiers in charge of transporting and guarding ammunition were amongst the first to be issued self-igniting guns like the wheellock and snaphance.

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Wikipedia