Snaphance

A snaphance or snaphaunce is a type of lock for firing a gun or is a gun using that mechanism. The name is Dutch in origin but the mechanism can not be attributed to the Netherlands with certainty. It is the mechanical progression of the wheellock firing mechanism, and along with the miquelet lock and doglock are predecessors of the flintlock mechanism. It fires from a flint struck against a striker plate above a steel pan to ignite the priming powder which fires the gun. Examples of this firearm can be found through Europe, North Africa, and the Middle East.

Like the earlier snaplock and later flintlock, the snaphance drives flint onto steel to create a shower of sparks to ignite the main charge (propellant).

The flint is held in a clamp at the end of a bent lever called the cock. Upon pulling the trigger, this moves forward under the pressure of a strong spring and strikes a curved plate of hardened steel (called simply the steel, or in 17th century English dialect the frizzen) to produce a shower of sparks (actually white-hot steel shavings). These fall into a flash pan holding priming powder. The flash from the pan travels through the touch hole to cause the main charge of gunpowder to explode. The steel is at the end of an arm that can be moved independently of the pan cover.

The snaphance first appeared in the late 1550s as an improvement of the earlier snaplock in one or more of the following countries: Spain, Holland, Germany, Scotland, or Sweden. The main improvement was that the pan-cover opened automatically (to keep the priming dry until the exact moment of firing), as in the wheel-lock. (The snaplock had a manually operated pan cover similar to that of the matchlock. Some definitions class the snaphaunce as a sub-type of snaplock.) Also like the wheel-lock, the snaphance used a lateral sear mechanism to connect trigger to cock. Later models had a variety of safety mechanisms to prevent accidental discharge of the gun. Without these the weapons, like any firearm, could be highly dangerous: Hakluyt's "Voyages" records the death of one of the men on Cavendish's circumnavigation in the 1580s due to an accidental discharge during a hurried re-embarkation on the coast of Ecuador, specifically mentioning the weapon was a snaphance. The snaphaunce has a form of safety built into its design, since the steel (frizzen) could be manually moved forward so that if the cock should be released accidentally it would not strike sparks. This led to an inherent disadvantage: in the flintlock when at half-cock and the frizzen is closed, the flint is in close proximity to the steel and can easily be adjusted to strike square to and in the center of the steel; in the snaphaunce the cock can only be at full-cock or down, where it prevents the steel from being brought back to the firing position, so the flint is more difficult to align. The development of the snaphance occurred separately but at the same time as the creation of the miquelet.

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