When was smokeless powder introduced

Those byproducts catalyze the further deterioration, increasing its rate. The released heat, in case of bulk storage of the powder, or too large blocks of solid propellant, can cause self-ignition of the material.

Single-base nitrocellulose propellants are most susceptible to degradation; double-base and triple-base propellants tend to deteriorate more slowly. To neutralize the decomposition products, which could otherwise cause corrosion of metals of the cartridges and gun barrels, calcium carbonate is added to some formulations. To prevent buildup of the deterioration products, stabilizers are added. Others are 4-nitrodiphenylamine, N-nitrosodiphenylamine, N-methyl-p-nitroaniline, and diphenylamine.

The stabilizers are added in the amount of 0. The amount of the stabilizer is depleted with time. Propellants in storage should be periodically tested on the remaining amount of stabilizer, as its depletion may lead to autoignition of the propellant. The propellant formulations may contain various energetic and auxiliary components:.

The properties of the propellant are greatly influenced by the size and shape of its grains. The surface of the grains influences the speed of burning, and the shape influences the surface and its change during burning. By selection of the grain shape it is possible to influence the pressure vs time curve as the propellant burns.

Faster-burning propellants generate higher temperatures and higher pressures, however they also increase the wear of the gun barrels. Categories: Cordite Firearm propellants. Read what you need to know about our industry portal chemeurope.

My watch list my. My watch list My saved searches My saved topics My newsletter Register free of charge. Keep logged in. Cookies deactivated. To use all functions of this page, please activate cookies in your browser.

Login Register. Additional recommended knowledge. Topics A-Z. All topics. To top. About chemeurope. Colorimetry-Software Day Free Trial.

Your browser is not current. Microsoft Internet Explorer 6. The way it works is that even though the propellant has a high explosive substance, a stabilizing chemical is also added to slow down the burn rate of the high-explosive so that it behaves more like a low-explosive.

The first smokeless powders were made in , when both nitrocellulose gun cotton and nitroglycerine were first developed in Europe. The invention of gun cotton was actually the result of a happy accident. A Swiss scientist named Christian Schonbein was forbidden by his wife from conducting chemistry experiments at home, but he didn't always obey her.

One day in when she was away, he accidentally spilled a mixture of strong nitric and sulfuric acids in the kitchen. He quickly wiped the mess up with his wife's cotton apron and then hung it over the stove to dry.

To his surprise, the apron ignited and disappeared almost instantly, leaving behind almost no ashes. What Schonbein had done was accidentally manufacture nitrocellulose. Soon, with the help of another professor, he came up with the recipe of one part of fine cotton fibers, combined with fifteen parts of an equal blend of sulfuric and nitric acids.

The cotton is dipped in the acid mixture for two minutes and then washed in cold water to remove any acids. Then the cotton is dried at moderate climate temperatures to form nitrocellulose. This material provides less heat and smoke and upto six times the explosive force of the same volume of black powder.

However, guncotton was notoriously unstable and therefore, the British, French and Prussian governments stopped using it soon after.

However, the French continued to perform experiments to improve its stability. In , a French chemist named Paul Viellie succeeded in improving guncotton's stability issues. He discovered that by treating guncotton with a mixture of alcohol and ether, it could be gelatinized. This formulation was codenamed Poudre B by the French government and it was a closely guarded secret.

This formula produces a substance that is much more stable than guncotton and it will not detonate unless it is compressed. Unlike black powder, Poudre B also burns when wet and produces about three times the force for the same volume. This was the first "single-base" powder. The French developed the 8 mm.

Lebel cartridge the first smokeless military cartridge and a new rifle, the Lebel Model to use this new technology. In , Alfred Nobel the same person who started the Nobel prizes discovered that he could gelatinize nitrocellulose by using nitroglycerine. He started to market his invention as " Ballistite " and it was the first "double-base" powder. The presence of nitroglycerine gave ballistite an even greater range than Poudre B.

Nobel Industries set up a plant in Scotland to manufacture ballistite. In the very next year, the British government appointed an "Explosives Committee" to monitor and study developments in other countries. They obtained samples of Poudre B and Ballistite, but decided that neither was suitable for adoption in UK. From the cord, small pieces and shavings could be cut mechanically using a knife or a file, or it could be ground up using a device similar to a coffee grinder.

In most cases, it was cut into small strings and packed into a cartridge case like spaghetti. This material was naturally given the name " cordite ". It is also a double-based explosive like ballistite and later, a triple-base cordite was also invented. Abel and Dewar were the target of a lawsuit by Alfred Nobel, who felt that they had merely modified Ballistite slightly.

The case took several years to be resolved and eventually reached the House of Lords, where the court ruled in favor of Abel and Dewar. Disassembled cartridge. Note the light brown strings of cordite which were packed inside it. An interesting feature of cordite and some other smokeless powders as well is that if the strings are burnt outside the cartridge, then they burn rather slowly with a yellow flame and no explosion.

After cooling of the medium, and when the grains have become consolidated or hardened, they may be subjected to a screening operation, in which the oversizes can be sent back for reworking and the screened grains can be subjected to a wringing operation and thereafter to a drying operation.

The grains may be surface treated prior to drying with a suitable modifying agent, such as a deterrent or an accelerator. The coating may comprise nitroglycerin which acts as an accelerator; in that it allows the powder to be more readily ignitable and also acts as a waterproofing agent, rendering the powder non-hygroscopic.

A suitable deterrent such as dibutylphthalate may be used along with the nitroglycerin or other accelerator and waterproofing agent. The grains may be then dried and glazed in the usual manner and thereafter blended if desired Olsen et al. The size of the grains is a function of the extent and the violence of the agitation as well as the amount of protective colloid and the viscosity of the dissolved base Olsen et al.

The grain size decreases with the increase of rotor speed, the increase of percentage of the colloid and the viscosity of the nitrocellulose. Furthermore the amount of solvent employed affects not only the size, shape and surface of the resultant grains, but also the gravimetric density thereof Schaefer Schaefer HF, inventor; May Small amounts of solvent give a small rough cluster of particles as the grains while larger amounts of solvent give more spherical smoother grains.

The rate at which the temperature is raised during evaporation of the solvent affects both the granulation and density of the resultant powder Schaefer Schaefer HF, inventor; May The process for the manufacture of spherical powder, which Olsen and his co-workers have devised, combines nicely with Olsen's process for the quick stabilization of nitrocellulose to form a sequence of operations by which a finished powder may be produced more rapidly and more safely than by the usual process.

It supplies a convenient means of making up a powder which contains nonvolatile solvents throughout the mass of the grains or deterrent or accelerant coatings upon their surface Urbanski Urbanski T Chemistry and technology of explosives.

Warszawa: Polish Scientific Publishers. Although the spherical powder starts as pure nitrocellulose, the finished product is a double-base propellant, since nitroglycerin is added after shaping and its content is created by surface impregnation.

Table 1 provides a comparison between spherical powders and other common double-base smokeless powders with respect to manufacture process, characteristics and uses. It aims to briefly compare spherical powders against other double-base propellants. This is important since their production is more complex hence expensive than that of extruded propellants.

Due to this, they are used mainly when the ammuntion does so requires. Another important comparison aspect between propellants is the effectiveness and burning characteristics. This comparison is carried out using Fig. Progressive burning occurs when the thrust produced increases with time and with distance traveled, inside the barrel Kosanke Kosanke K Terminology of model rocketry; [accessed Nov 15].

During a regressive burning, the surface area decreases with time, and so does the thrust. The neutral burning happens when the burning area is approximately constant, which results in a constant thrust over the burning period. The pressure peak is higher and is reached first in a regressive burning rate because, as the burning area decreases, the gas production lowers, so the maximum pressure occurs in the very beginning of the barrel.

On the other side, if a progressive burning propellant is used, the peak pressure is limited to a value that may be tolerated by the gun Moss et al. London: Pergamon Press. It is also important to address the effect of adding high explosives in the composition on the propellant performance Zhu et al. Figure 2 Pressure-time curves for different burning rates. In Fig. The curves shown in Fig. The spherical powder can be used in small ammunitions to provide a greater muzzle velocity, which will result in a bigger kinetic energy being transferred to the target.

A typical peak pressure for a 5. The great advantage of the spherical powder manufacture process is the possibility of using deteriorated and unstable nitrocellulose. Aged powders that would be destroyed can be reused, which results in a lower production cost. Also, the nitrocellulose stabilization process, that requires a big quantity of water and energy, is not necessary since the process of making the propellant spherical already stabilizes the nitrocellulose.

Hence the process to make the powder spherical substitutes the stabilization process. One disadvantage is the fact that the spherical powder production plant cannot be used to manufacture other types of powder, due to the specificity of equipment and the lack of machinery to extrude propellants. Regarding ballistic characteristics, the spherical powders are appropriate for use in small ammunitions usually up to mm caliber rounds because of their progressive burning rate and high loading density, which will result in a high muzzle speed.

It is therefore undeniable that they are very important in the propellants field and should not be neglected by ammunition and propellant industries. This is major when it comes to small rounds that benefit most from the burning behavior of the spherical powder. Open menu Brazil. Journal of Aerospace Technology and Management. Open menu. Text EN Text English. Table 1 Comparison between spherical powders and common powders. Barzanjy MJ Life cycle and performances progressing of artillery barrels.

Boddicker FL, inventor; Aug 6. Coffee RE; inventor; Jan Department of the Army Hodgdon Powder Co. Kosanke K Terminology of model rocketry; [accessed Nov 15]. United Nations UN recommendations on the transport of dangerous goods - model regulations. Urbanski T Chemistry and technology of explosives. Publication Dates Publication in this collection Oct-Dec History Received 15 Feb Accepted 02 Nov This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Figures 2 Tables 1. Powder Advantages Disadvantages Spherical powder Unstable nitrocellulose can be used.