matchlock

The matchlock was the first mechanism invented to facilitate the firing of a hand-held firearm. Before this, firearms (like the hand cannon) had to be fired by applying a lit match (or equivalent) to the priming powder in the flash pan by hand; this had to be done carefully, taking most of the soldier's concentration at the moment of firing, or in some cases required a second soldier to fire the weapon while the first held the weapon steady. Adding a matchlock made the firing action simple and reliable by a single soldier, allowing them to keep both hands steadying the gun and eyes on the target while firing.

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