A snaplock is a type of lock for firing a gun or is a gun fired by such a lock. A snaplock ignites the weapon's propellant by means of sparks produced when a spring-powered cock strikes a flint down on to a piece of hardened steel. The snaplock is therefore similar to the snaphaunce and the later flintlock. In all snaplocks, the flint is held in a clamp at the end of a bent lever called the cock. When the gun is "cocked", the cock is held back, against the pressure of a spring, by a catch which is part of the trigger mechanism. When the trigger is pulled, the catch is released and the spring moves the cock rapidly forwards. The flint strikes a curved plate of hardened steel, called the "steel". The flint strikes from the steel a shower of white hot steel shavings which fall towards the priming powder held in the flash pan. The flash from the pan's ignited primer travels through the touch hole into the firing chamber at the rear of the barrel, and ignites the main charge of gunpowder. Before the weapon is fired, the pan has a closed cover: the mechanism for opening this cover can affect whether the weapon is classed as a snaplock. In fact, the term snaplock may be used in three ways, as follows:
The most general use of snaplock is for any lock which strikes flint against steel but which does not have the defining feature of a true flintlock. This is the frizzen, a single piece of metal which is a combined "steel" and self-opening pan cover.
A more restrictive definition excludes the snaphaunce, more sophisticated weapons with a lateral sear and a pan cover, separate from the steel, that opens automatically.
Sometimes the term is used only for specific Scandinavian, German, and Russian varieties of lock.
Period of use
The snaplock first appeared in the late 1540s, probably in southern Germany. It was cheap and easy to produce, and like all post-matchlock weapons, could be primed and loaded in advance and be fired at a moment's notice. It fell out of favor by about 1640, except in Sweden and Russia, where it lasted far longer.
Safety
Snaplocks as a class did not have safety devices, but individual models could be prevented from inadvertent firing by different mechanisms:
In the early models with a manual pan cover, the steel could be swung out of the path of the flint until just before firing; also, a closed pan cover would not allow the primer to ignite and could help keep the primer dry in misty conditions.
On some models, an externalhook attached to the lock plate could engage the tip of the "cocked" cock to prevent it from moving forwards.
