This weapon proved especially good in defensive battles to protect castles and fortresses. It was here that the advantages of this weapon in the power and accuracy of the shots were especially important, and the lack of rate affected the least.
Simplifying a little, we can say that a crossbow is a bow mounted on a bed, equipped with a latch and a trigger. A bow, including a crossbow, is an elastic arc, the ends of which are connected by a stretched bow. Before cocking, the ends of the arc are maximally apart, the string tension is minimal. When cocking, the bowstring is pulled along the bed and in a tense, state is fixed with a latch. The arrow is placed in the guide groove on the bed.
The shooter takes aim and with the help of the trigger releases the bowstring. The bow of the crossbow is straightened, its bow is extended, and the arrow flies to the target. This is a universal crossbow operation scheme, starting from the fourth century BC until today.
But there have been many changes over the twenty-five centuries of the existence of these weapons: in design, in technology, and in use. In this article you will know about Parts of a Crossbow.
History of creation
Historians cannot agree on whether the crossbow was coined in ancient Greece or in ancient China. It is likely that this happened in Europe and Asia almost simultaneously.
The idea of inserting a wand between the center of the bow arc and a taut bow so that you do not have to hold a stretch with your hands during aiming is almost commonplace. She could well have come to the heads of many at the same time.
But the crossbow really became in demand around the 11th century. In those days the typical nature of hostilities changed. Many feudal wars were fought around defense and the capture of then stone fortresses that appeared everywhere. It was for the defense of fortresses that this weapon was the best suited.
The difficulties of its combat use in attack are that the crossbow limits the mobility of the warrior: it takes time to reload and leaves the shooter defenseless at that moment. In the defense of a reliable stone fortress, the situation is different. Recharge occurs in safety, under the cover of a stone wall. The crossbow is an excellent defensive weapon. The period from the XI century to the XVI century accounts for the era of the crossbow. It ended only with the advent of military firearms.
The main design of the device
The crossbow consists of:
- The bed to which the bow and the trigger are attached;
- A bow, often consisting of two shoulders and a block between them;
- Bowstrings, which are usually made from a synthetic polymer;
- Trigger with bowstring lock and trigger;
- Scope, usually located on the Picatinny rail.
Details in the parts of a crossbow
Lock
The main Parts of a Crossbow is Lock. The lock fixes the bow of the crossbow in a cocked state. The principle of its operation is based in one form or another on a design invented by the ancient Chinese: a bowstring, when cocked, snaps a “nut” on a spring-loaded trigger. Subsequently, this design was continuously modernized, complicated, overgrown with adjustments, fuses, and additional parts to facilitate descent. On expensive sports models, even an electronic trigger is not uncommon.
In contrast to the fire trigger, in which a lot of force is not required to hold the “striker”, the details of the crossbow’s castle account for all the power of its shoulders, therefore high-strength steel is most often used for their manufacture, less often titanium or composite materials. Although some “craftsmen” are trying to make castles of aluminum – they do not live for a long time and, as a rule, except for injuries, they do not deliver other joys to their owners.
Lodge
The stock is the base of the crossbow. It is the design and materials of the box that determine the convenience, comfort and appearance of the entire crossbow. For the hunter, the bed will be light and applied, for the athlete – long and heavy, with many adjustments, in the gift design – expensive and beautiful, with thread and inlay, and for children – small and safe, pistol type.
The most suitable material is wood or glued veneer. Plastic is not welcome. But not every tree is suitable for creating a lodge, it is best to use walnut, oak, mahogany, that is, strong and viscous varieties of wood for these purposes.
Shoulders (arcs)
Crossbow shoulders are the elastic elements of a bow that accumulate the mechanical energy of a person produced during tension for a subsequent shot. The shoulders are attached directly to the bed, on powerful crossbows – to the bed through a metal block (5). Designs of crossbow bows are divided into traditional and block.
In turn, the shoulders can be straight or curved (recursive), have a monolithic or separate structure.
The traditional design is an ordinary bow in our understanding, the ends of which are connected by a bowstring. In a block structure, blocks (round or eccentric) are fixed at the ends of the shoulders, through which the bowstring is passed. Due to these blocks, the process of cocking a crossbow is greatly simplified, while the power of the shot remains the same.
The most common materials for the production of shoulders – fiberglass reinforced, carbon fiber with carbon fiber, duralumin. Previously, when the materials were “strained”, old spring from Moskvich was used as a blank for onions. Not only was such a crossbow incredibly heavy and massive, it was traumatic, since steel tended to burst at the most inopportune moment, flying apart with sharp fragments in different directions. Therefore, subsequently they began to put on a protective bandage on such bows, and then completely abandoned this material.
Shoulders (arcs)
Crossbow shoulders are the elastic elements of a bow that accumulate the mechanical energy of a person produced during tension for a subsequent shot. The shoulders are attached directly to the bed, on powerful crossbows – to the bed through a metal block (5). Designs of crossbow bows are divided into traditional and block.
In turn, the shoulders can be straight or curved (recursive), have a monolithic or separate structure.
The traditional design is an ordinary bow in our understanding, the ends of which are connected by a bowstring. In a block structure, blocks (round or eccentric) are fixed at the ends of the shoulders, through which the bowstring is passed. Due to these blocks, the process of cocking a crossbow is greatly simplified, while the power of the shot remains the same.
The most common materials for the production of shoulders – fiberglass reinforced, carbon fiber with carbon fiber, duralumin. Previously, when the materials were “strained”, old spring from Moskvich was used as a blank for onions. Not only was such a crossbow incredibly heavy and massive, it was traumatic, since steel tended to burst at the most inopportune moment, flying apart with sharp fragments in different directions. Therefore, subsequently they began to put on a protective bandage on such bows, and then completely abandoned this material.
Stirrup
Crossbow stirrup is designed to facilitate the cocking process. The stirrup is loop-shaped and T-shaped. In both cases, the arrow’s legs hold the crossbow by the stirrup, while the bowstring is being tensioned.
Cam
The cams in each compound crossbow have wheels at the end of each limb. The string is attached to the cam. The wheels turn when it is pulled. These wheels can be round or oval in shape.
Block
The block is the second most important crossbow after the castle. This element plays a connecting role between the shoulders and the rest of the crossbow. It is the block that accounts for the entire load of arcs in their pure form. It is the block that must withstand enormous loads during the shot. It is the block that accounts for all the energy of the so-called “backward recoil,” when the arrow has already flown out, and the shoulders continue to straighten out with great speed.
Therefore, the block is given so much attention. Usually high-strength steel is used for the pads, titanium is used on expensive crossbows. Although I sometimes met crazy mount designers who put an aluminum profile block on their 80 kg crossbows. And then they wondered why, after a dozen shots, she was turned inside out.
Bowstring
The bowstring of modern crossbows is a several times folded string with subsequent braiding of the rubbing parts. In the best way for a bowstring, a strong and low-stretch thread, such as dacron, lavsan, aramid thread (in common people – Kevlar) or a foreign analog Fast-Fligh. On powerful crossbows, as well as on auxiliary strings of block crossbows, a steel cable is used.
Guide
The crossbow guide, as the name implies, is designed to hold the arrow and direct it toward the target. In medieval crossbows, the gutter was made either directly in the bed, or in the form of a bone lining with a gutter. On the simplest modern crossbows, a plastic guide is glued directly on top of the stock. On more “advanced” ones, the guide plate is made of a material with sufficient antifriction properties so that the arrow moves along it easily and evenly, and the bowstring would wear off as slowly as possible.
In systems with high tension, it is even recommended to use oil to lubricate the guide. Such a guide is fixedly attached to the crossbow body or use two guide plates located at some distance from each other. Regarding the distance between the guides (groove), then its size depends on the diameter of the arrows used, as well as the height of the plumage. As a rule, the width of the groove (with chamfers removed) should be such that the axis of the arrow intersects the center of the bowstring, which in turn should lie (without vertical force) on the upper surface of the box and move parallel to it when fired.
Sight
Due to the steep trajectory of the boom, the installation and arrangement of crossbow sights have their own characteristics. Used sights are divided into three categories: open, diopter and optical.
Below we will consider each of them individually, together with the design features in more detail.
Open. This design is a development of the idea of a beam sight. The fixed rear sight is complemented by a console mounted next to the bow, on which a set (three to five pieces) of horizontal flies (each with horizontal and vertical adjustment) is attached for different firing distances (the so-called “comb”). When aiming, the shooter selects the desired front sight in height, depending on the firing distance.
Dioptric. Basically, these sights are placed on sports crossbows and in design coincide with the sights for bullet sports. All the differences are only in the front sight: it has a wide range of adjustments and can be equipped with a level level to control the “blockage” of weapons.
In addition, it is usually provided for the longitudinal inclination of the diopter and its front sight to eliminate the ellipse of the headphone when they do not coincide in height. On the other hand, there is a tendency to move away from the gunshot ideology of aiming. Now they prefer to carry out all micrometric adjustments on the fly, while the diopter itself remains motionless.
Optical Existing developments for bullet weapons are quite suitable for installation on crossbows. It is only necessary to remember that the mount has a bevel towards the target of the order of one or two degrees.
Cables
In the design of block crossbows, they pairwise connect blocks with opposite shoulders and intersect in a special hole in the crossbow body. The cables are made of the same materials as the bowstring and you also need to take care of them.
Runner (in the construction of block crossbows)
At the intersection of the cables in the crossbow housing there is a special plastic runner that prevents the cables from rubbing against each other. In no case should you underestimate the importance of this detail. If you forget to install it when assembling the crossbow, the cables will break in five to ten shots.
We got acquainted with the device of the front of the crossbow, now we move on to the description of the remaining details.
Aim bar
Above the trigger is a universal sighting bar of the “Weaver” or “Picatinny” type. Therefore, on all modern crossbows, you can install any type of sight. The aiming bar can be adjusted vertically, and it can be installed rigidly.
Pressure bar
The next small but important detail is the clamping bar. It holds the boom at the time of aiming, and also ensures its uniform fit to the guide. Structurally, it is just a flexible metal spring, however, there are trims with a pile (bristle) or with a spring-loaded ball.
The handle
The handle and trigger are located either immediately below the trigger, or they are pushed towards the front of the trigger relative to the trigger (Bull-pub system). In fact – the handle of a crossbow is no different from the handle of any other firearm or pneumatic weapon.
Handguard
The forearm, as befits a forearm in any other type of small arms, is located on the bottom of the crossbow body between the front of the crossbow and the handle. The forearm can be part of the crossbow, can be separate, but fixed, and can be interchangeable and rearranged depending on the convenience of the shooter. Often in modern crossbows, the forearm is attached to the body with the help of a weaver strap, which allows you to choose any type of forearm, a convenient arrow.
Butt
The stock serves to rest the crossbow in the shooter’s shoulder during aiming. There is a complete analogy with other types of small arms. The stock can be part of the crossbow, can be adjustable or even interchangeable.