Radschloss

German Radschloss combined Rad (wheel) and Schloss (lock, fastening). The wheellock mechanism, invented around 1510–1520 (possibly by Leonardo da Vinci, though his notebooks' designs were never published and may not have influenced the actual invention), used a serrated steel wheel wound with a key. When the trigger released the wheel, it spun against a piece of iron pyrites, generating sparks that ignited the priming powder.

The wheellock's significance was strategic: it produced fire on demand without requiring a continuously burning match. A cavalry officer could carry a loaded, primed wheellock pistol in a holster and fire it immediately — impossible with a matchlock, which required a burning slow-match to be held ready. The cavalryman's pistol emerged directly from the wheellock's self-contained ignition.

Wheellocks were expensive — the mechanism required skilled metal work — and complex. They were carried by cavalry officers and noblemen. The 'Reiters' (German horse pistoleers) who developed caracole tactics in the 16th century — riding to close range, discharging pistols in sequence, then retreating — required the wheellock's reliability. Decorated wheellock pistols survive as art objects: many in Vienna's Kunsthistorisches Museum are masterpieces of Renaissance metalwork.

The flintlock, developed around 1610–1630, used a simpler mechanism — a piece of flint held in a cock, striking against a steel frizzen — and replaced the wheellock in military use. Cheaper and easier to maintain, the flintlock served armies until percussion caps arrived in the 1840s.