Wheellock

A wheellock, wheel-lock or wheel lock, is a friction-wheel mechanism to cause a spark for firing a firearm. It was the next major development in firearms technology after the matchlock and the first self-igniting firearm. The mechanism is so-called because it uses a rotating steel wheel to provide ignition. Developed around AD 1500, it was used al...
Found on http://en.wikipedia.org/wiki/Wheellock

wheellock

an obsolete mechanism for firing a firearm.
Found on http://en.wikipedia.org/wiki/Glossary_of_firearms_terms

Wheellock

An early system of ignition for muzzle-loading firearms where a steel wheel is wound up a partial turn against a spring and set with a catch. An arm, holding a flint, is manually lowered to the edge of the wheel. Upon the pull of a trigger, the wheel revolves smartly, producing sparks which ignite the main propellant charge. Photo
Found on http://www.hallowellco.com/abbrevia.htm

Wheellock

An ignition mechanism for firearms using a spring-driven steel wheel to generate sparks from a piece of iron pyrites to ignite the priming powder.
Found on https://www.royalarmouries.org/collections/glossary
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