The invention of the capsule forever changed the world of firearms. Increasing the rate of fire, he also increased the reliability of muskets and pistols that were used centuries ago on the battlefields. Today, the igniter capsule is an integral part of any cartridges - smooth-bore and rifled, small .22 LR and large-caliber 12.7 mm. Of course, many gun lovers would be interested to learn about the history of his invention, as well as the main varieties.
History of capsule
To begin with, the igniter capsule was first made in 1814 by the American specialist D. Shaw. It had exactly the form that many shooters are used to seeing today - a small metal container filled with a mixture of explosive mercury and brown water salt.
However, it was not used as it is today. The capsule just fit on a special ledge - a brandtube, which was located directly above the seed hole in the barrel.
Yes, it was not too convenient. But earlier, the shooters had to pour gunpowder on the shelf, and then set fire to it. The slightest wind, not to mention the rain, made shooting from a firearm very difficult. Therefore, the statement that the capsule revolutionized the weapons world is not under discussion.
Why is it needed?
The answer is as simple as possible. The capsule is used in modern cartridges to set fire to gunpowder. An open flame bursting out by a tiny directed explosion effectively copes with the task.
But as practice shows, it allows you to achieve a different, side effect. It is this explosion that significantly increases the pressure in the cartridge case, providing even faster and more efficient burning of gunpowder. Of course, this leads to an increase in the power of the shot and the range of the bullet (fractions or buckshot).
Device
Conventionally, all capsules used today can be divided into two types: open and closed. The former are direct descendants of the brainchild of D. Shaw, but the development of the latter was laid by the French engineer Zhevelo, who created a very different igniter capsule device closer to the end of the nineteenth century. By the way, the invention was named after this engineer, thanks to which every shooter knows him today.
The open type capsule is a red cap made of copper, on the bottom of which an explosive is laid (we will talk about it later). To protect it from moisture, aluminum foil is fixed on top, fixed with a special varnish. The hole in the sleeve, designed for installation of the igniter, is equipped with a small ledge - anvil. Explosive substance when installing the capsule abuts against it. Upon impact, the striker, when caught, is ignited, setting fire to the powder through two holes the thickness of a needle.
A completely different device has a chewing capsule. The cartridges with which it is used do not have an anvil. But it is part of the capsule itself. A pointed metal object is located inside the structure, which significantly increases the size. The increased complexity of manufacturing is the reason for a marked increase in cost. But reliability also increases dramatically. In addition, the ability to abandon the anvil in the sleeve allows the flame to break through not through two tiny holes, but through one, but equal in size to the capsule itself. Of course, this provides not only a more powerful ignition, but also a sharp increase in pressure. Therefore, gunpowder burns even faster, and the charge flies to a greater distance with less persistence.
Explosive
Of course, when talking about the igniter capsule, one cannot help but mention its composition. More specifically, the explosive used in it.
In the first capsules, as mentioned above, a mixture of bertholate salt and detonating mercury was used. It was perfect for black powder. But for modern cartridges that use smokeless powder, this composition is no longer suitable. The fact is that the ignition reaction proceeds too quickly and almost without gas evolution. Because of this, the pressure in the liner does not increase, and the powder does not always burn completely without a trace. Therefore, today antimony is also added to the classic recipe. Thus, the composition of the explosive is obtained as follows:
- 35% of explosive mercury - thanks to it, the ignition itself takes place;
- 40% of brown-haired salt - when burned, it decomposes, releasing the oxygen necessary to ignite the powder;
- 25% antimony, which significantly increases the combustion temperature of the mixture.
The exact proportions are extremely important - any violation of technology leads to the fact that the capsule will not be able to effectively cope with its task. Some experts argue that making it is much more difficult than, for example, a camera. Therefore, it is simply impossible to create a self-igniter capsule.
A little about the types of capsules "Zhevelo"
As mentioned above, all capsules can be divided into two types: open and closed. The last one is Zhevelo - it is mainly used for hunting weapons.
In recent years, demand for them is constantly growing. The fact is that most hunters today refuse to use expensive brass sleeves, preferring plastic ones. Although they can be used only a few times (and are often thrown out after the first shot), they are much cheaper, and there is no need to recharge. It was demand that led to the fact that various modifications appeared on the market. For example, on sale you can see the KV-209, KV-21, KV-22 igniter capsule. By the way, the 21st is a legacy of Soviet times, and the 209th appeared relatively recently.
What to say about the centrifuge
But the popularity of a centrifugal igniter among fans of smoothbore weapons is falling. Despite its simplicity and cheapness, it cannot provide such quick and powerful burning of gunpowder, so the demand for it is reduced. But the use of a centrifuge in rifle cartridges ensures that it disappears very soon. Even a cartridge of 7.62 caliber, not to mention 5.56, contains a much smaller amount of gunpowder than, for example, 12 or 16 caliber. Therefore, here the centrifugal capsule does an excellent job.
The analogue of the Boxer system is very similar to a centrifuge capsule - having exactly the same device, they differ only in the absence of a positioning welt. But these samples are used mainly in the United States, where the independent equipment of cartridges for rifled weapons is legal.
Of course, if you paint all kinds of igniter caps by numbers, it will take another article. But what has already been said is enough for the reader to get an idea about this difficult, but integral component of the modern cartridge.
Conclusion
The article is drawing to a close. Now you know the composition of the igniter capsule, its history, as well as the main varieties. We hope this information will be useful to you and will allow you to better understand the world of weapons and everything related to it.