A very interesting conversion pistol.

Here it is, the pistol we're talking about. It's a percussion cap pistol, but its lock is from a flintlock pistol. Weight: 1 kg. Caliber: 15,7 mm. Photo by the author.
The frost is silvery…
Junker Schmidt from a pistol
He wants to shoot himself.
Junker Schmidt. Kozma Prutkov
stories about weapons. No matter what you say, life is much more interesting now than it was in the past. Back then, it was like this: you can't go here, you can't go there. But now, so many things that were once forbidden are now possible. For example, I wanted a Nepalese kukri—I ordered one, and they sent it to me. And a good friend of mine collects rifles and pistols and... he can buy practically anything, it's just a matter of money. And recently, you could say he got very lucky, because there's no other way to put it: he managed to buy a cap pistol, converted from a flintlock. And not just any flintlock pistol, but a miquelet pistol, a very rare and therefore valuable item. And so interesting, in fact, that today, dear readers of VO, I'll tell you about this pistol in detail, and show you the pistol itself in every detail.
But first, a little bit stories, because it's also quite interesting. It so happened that during Emperor Charles V's Algerian campaign of 1541, weather conditions (torrential rain and icy wind) made firing arquebuses impossible. Moreover, accidents arose with both wheellock and matchlock weapons. First, the wind blew the powder off the pan as soon as the lid was opened, and second, the powder in the priming powder became wet in the rain. It's no surprise that people began to consider these problems and began improving the flintlock. It's no coincidence that the earliest mention of the miquelet-type lock appeared in Spain, three decades after the military disaster in Algeria.
This type of lock is also called a Mediterranean lock, but the name "miquelet," which translates from Spanish as "militia" or "people's militia," is also popular. However, the term itself appeared no earlier than the 19th century and was associated with the English troops participating in the Peninsular Campaign against the Napoleonic Wars. At that time, locks of this type were used by Spanish militias fighting against the French. The British, who were not very fluent in Spanish, christened the ignition mechanism, which was new to them, with this name. The miquelet is often called a "Mediterranean lock" due to its widespread use in regions adjacent to the Mediterranean, especially those within the spheres of influence of Spain and Turkey. Initially, the new lock spread across the Mediterranean, while the Spanish lock found its way to Turkey, Western Asia, Arabia, and, along with Turkish warriors and their weapons, to Russia.

Spanish patilla lock inlaid with gold and silver, late 17th century. Cleveland Museum of Art
In Spain, it was also known as the "llave española" or simply "patilla." Today, the word "patilla" is often used instead of "miquelet." The term "patilla" derives from the resemblance of one of the lock's components to a chicken's foot. In Catalonia, it was called the "clau de miquelet" ("miquelet key"). In Portugal, it was known as the "fecho de patilha de invenção" ("snap lock").

A patilla being converted into a cap lock. Photo by Helen Rival.
When examining the patilla design, one cannot help but admire its simplicity. All the components of this lock are located on the outside of the lockplate, and in a very compact arrangement. Only two horizontal sears are located on the inside of the plate. While this exposes the lock components to the elements and increases the risk of damage from accidental impacts, it also makes it easy to detect and repair any malfunctions. It's no coincidence that this type of lock remained in service for a record-breaking length of time—in several countries in Africa and Asia, as well as in the Caucasus, patilla-equipped weapons continued to be manufactured until the 20th century.

Miquelet lock diagram
Let's look at the diagram of the miquelet lock shown below: the mainspring (highlighted in blue) is located on the outside of the lockplate and occupies almost its entire length. It presses downward on the heel of the hammer (shown in bright green), passing under the "bridge" (dark green), which securely attaches the hammer to the lockplate. When the hammer is cocked, its curved toe rests against one of two horizontal sears running through the lockplate (the upper one is red, the lower one is yellow). To allow free movement, the toe of the hammer is flat, and the mainspring is spaced from the lockplate just enough for the toe to pass. The upper sear holds the hammer cocked, while the lower one allows it to be set to half-cock. Moreover, experts note that there were two main modifications of the miquelet: the Spanish lock, in which the mainspring pressed on the heel of the rod, and two pins rested on its toe, and the Italian, or Roman, lock, in which the mainspring pressed on the toe of the rod, and the pins, on the contrary, rested on its heel.

The pistol is at half-cock. It's clearly visible that the mainspring has a rectangular cutout to allow the hammer to move freely. When the pistol was converted to a percussion cap pistol, the rear barrel was clearly cut off and replaced with a new one, complete with a fire tube. The fire starter, pan, and spring (shown in blue, purple, and black on our diagram) have been removed.
This design was inspired by the fact that Spanish gunsmiths, almost immediately after the advent of the flintlock, were faced with a serious problem of ensuring the safety and security of the primer. After pouring gunpowder into the pan, the shooter had to close it with the flintlock cover, but this required pulling the hammer back. Holding the hammer while lowering the flintlock cover dramatically increases the risk of an accidental discharge. Fully cocking the hammer places a heavy load on the mainspring, shortening its lifespan and raising the possibility of an accidental discharge.

The trigger is pulled all the way, cocked, and nothing can interfere with its release!
Using a half-cock, which prevented sparks from forming even if the hammer were pulled, allowed the flint cover to be closed and the weapon to be carried safely. Before firing, the shooter cocked the hammer fully in one motion—the hammer, fully pulled back, gained enough speed upon falling to both flip the flint cover open and create sparks.

The hammer struck the fire tube on the barrel. The tip of the hammer passed over the retracted upper and lower sears.
Two horizontal sears were linked kinematically. When the trigger was pulled, it pressed on the horizontally curved tail of the half-cock sear (highlighted in yellow in the diagram), moving it out of the plane of the hammer's movement (highlighted in green). Simultaneously, the vertical projection of the half-cock sear (not visible in the diagram) pressed on the end of the full-cock sear, also moving it out of the hammer's plane of movement. By the time the hammer was released from the full-cock position, both sears were recessed into the lock plate.

A pistol. Left side view. The barrel is branded with a lily.
The simplicity of the patilla was so beloved by Caucasian gunsmiths that they used it as a basic design when transitioning to a fundamentally new ignition system. In the 19th century, a number of modified locks adapted for percussion cap ignition appeared in the Caucasus.

The octagonal barrel with smoothed edges has iron fittings, clearly a European workmanship, as brass was preferred in the East, but it's decorated with checkering. There's no front sight, suggesting this pistol was aimed at the barrel!

The trigger guard is decorated with engraving. A rectangular slot in the mainspring for the movement of the curved tip of the hammer is visible.

Attaching the cleaning rod to the fore-end

Cleaning rod (metal) and its dimensions
The trigger mechanism with a papilla-style hammer and Roman lock was used in pistols and hunting rifles until the advent of firearms chambered for single-piece cartridges. These trigger mechanisms with papilla-style hammers were often depicted with wild animals (lions, dogs, mythical beasts, or fish). Miquelets made in this style were especially common among Spanish gunsmiths from Eibar. This pistol is most likely their work. Moreover, the hammer is clearly made of a different metal than the lock pan, although it likely copied the shape of the previous flintlock. Due to the position of the fire tube, it also had to be curved!
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