A firearm is a portable gun that inflicts damage on targets by launching one or more projectiles driven by expanding high-pressure gas produced chemically by exothermic combustion of propellant within an ammunition cartridge. If gas pressurization is achieved through mechanical gas compression rather than through chemical propellant combustion the gun is technically an air gun, not a firearm; the first primitive firearms originated in 10th-century China when bamboo tubes containing gunpowder and pellet projectiles were mounted on spears into the one-person-portable fire lance, used as a shock weapon to good effect in the Siege of De'an in 1132. In the 13th century the Chinese invented the metal-barrelled hand cannon considered the true ancestor of all firearms; the technology spread through the rest of East Asia, South Asia, the Middle East, Europe. Older firearms used black powder as a propellant, but modern firearms use smokeless powder or other propellants. Most modern firearms have rifled barrels to impart spin to the projectile for improved flight stability.
Modern firearms can be described in the case of shotguns by their gauge. Further classification may make reference to the type of barrel used and to the barrel length, to the firing mechanism, to the design's primary intended use, or to the accepted name for a particular variation. Shooters aim firearms at their targets with hand-eye coordination, using either iron sights or optical sights; the accurate range of pistols does not exceed 110 yards, while most rifles are accurate to 550 yards using iron sights, or to longer ranges using optical sights. Purpose-built sniper rifles and anti-materiel rifles are accurate to ranges of more than 2,200 yards. Firearms include a variety of ranged weapons and there is no agreed upon definition. Many soldiers consider a firearm to be any ranged weapon that uses gunpowder or a derivative as a propellant. Small arms include handguns and long guns, such as rifles, submachine guns, personal defense weapons, squad automatic weapons, light machine guns; the world's top small arms manufacturing companies are Browning, Colt, Smith & Wesson, Mossberg, Heckler & Koch, SIG Sauer, Walther, ČZUB, Steyr-Mannlicher, FN Herstal, Norinco, Tula Arms and Kalashnikov, while former top producers were Mauser, Springfield Armory, Rock Island Armory under Armscor.
In 2018, Small Arms Survey reported that there are over one billion small arms distributed globally, of which 857 million are in civilian hands. U. S. civilians alone account for 393 million of the worldwide total of civilian held firearms. This amounts to "120.5 firearms for every 100 residents." The world's armed forces control about 133 million of the global total of small arms, of which over 43 percent belong to two countries: the Russian Federation and China. Law enforcement agencies control about 23 million of the global total of small arms; the smallest of all firearms is the handgun. There are two common types of handguns: semi-automatic pistols. Revolvers have "charge holes" in a revolving cylinder. Semi-automatic pistols have a single fixed firing chamber machined into the rear of the barrel, a magazine so they can be used to fire more than one round; each press of the trigger fires a cartridge, using the energy of the cartridge to activate the mechanism so that the next cartridge may be fired immediately.
This is opposed to "double-action" revolvers which accomplish the same end using a mechanical action linked to the trigger pull. Prior to the 19th century all handguns were single-shot muzzleloaders. With the invention of the revolver in 1818, handguns capable of holding multiple rounds became popular. Certain designs of auto-loading pistol appeared beginning in the 1870s and had supplanted revolvers in military applications by the end of World War I. By the end of the 20th century, most handguns carried by military and civilians were semi-automatic, although revolvers were still used. Speaking and police forces use semi-automatic pistols due to their high magazine capacities and ability to reload by removing the empty magazine and inserting a loaded one. Revolvers are common among handgun hunters because revolver cartridges are more powerful than similar caliber semi-automatic pistol cartridges and the strength and durability of the revolver design is well-suited to outdoor use. Revolvers in.22 LR and 38 Special/357 Magnum, are common concealed weapons in j
Stamping is the process of placing flat sheet metal in either blank or coil form into a stamping press where a tool and die surface forms the metal into a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, embossing, bending and coining; this could be a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or could occur through a series of stages. The process is carried out on sheet metal, but can be used on other materials, such as polystyrene. Progressive dies are fed from a coil of steel, coil reel for unwinding of coil to a straightener to level the coil and into a feeder which advances the material into the press and die at a predetermined feed length. Depending on part complexity, the number of stations in the die can be determined. Stamping is done on cold metal sheet. See Forging for hot metal forming operations. Stamped parts were used for mass-produced bicycles in the 1880s.
Stamping replaced die forging and machining, resulting in reduced cost. Although not as strong as die forged parts, they were of good enough quality. Stamped bicycle parts were being imported into the United States from Germany in 1890. U. S. companies started to have stamping machines custom built by U. S. machine tool makers. Through research and development Western Wheel was able to stamp most bicycle parts. Several automobile manufacturers adopted stamped parts before Ford Motor Company. Henry Ford resisted the recommendations of his engineers to use stamped parts, but when the company could not satisfy the demand with die forged parts, Ford was forced to use stampings. Over the history of metal stamping and deep drawing, presses of all types are the backbone of metals manufacturing; the processes continue to evolve and improve in moving more metal in one stroke of a metal stamping press. Press and interconnected automation devices increase production rates, reduce labor costs and provide higher safety levels for factory workers.
In today's metal stamping environment, controls such as I-PRESS with Connected Enterprise are able to capture history, send reports or the I-PRESS & Automation control can be viewed from remote or mobile devices. A new trend in gathering information on today's production for historical data. Bending - the material is deformed or bent along a straight line. Flanging - the material is bent along a curved line. Embossing - the material is stretched into a shallow depression. Used for adding decorative patterns. See Repoussé and chasing. Blanking - a piece is cut out of a sheet of the material to make a blank for further processing. Coining - a pattern is compressed or squeezed into the material. Traditionally used to make coins. Drawing - the surface area of a blank is stretched into an alternate shape via controlled material flow. See deep drawing. Stretching - the surface area of a blank is increased by tension, with no inward movement of the blank edge. Used to make smooth auto body parts. Ironing - the material is squeezed and reduced in thickness along a vertical wall.
Used for beverage cans and ammunition cartridge cases. Reducing/Necking - used to reduce the diameter of the open end of a vessel or tube. Curling - deforming material into a tubular profile. Door hinges are a common example. Hemming - folding an edge over onto itself to add thickness; the edges of automobile doors are hemmed. Piercing and cutting can be performed in stamping presses. Progressive stamping is a combination of the above methods done with a set of dies in a row through which a strip of the material passes one step at a time; the Tribology process generates friction which requires the use of a lubricant to protect the tool and die surface from scratching or galling. The lubricant protects the sheet metal and finished part from the same surface abrasion as well as facilitate elastic material flow preventing rips, tears or wrinkles. There are a variety of lubricants available for this task, they include plant and mineral oil based, animal fat or lard based, graphite based and acrylic based dry films.
The newest technology in the industry is polymer based synthetic lubricants known as oil-free lubricants or non-oil lubricants. The term "Water-Based" lubricant refers to the larger category that includes more traditional oil and fat based compounds. Sheet metal forming simulation is a technology that calculates the process of sheet metal stamping, predicting common defects such as splits, wrinkles and material thinning. Known as forming simulation, the technology is a specific application of non-linear finite element analysis; the technology has many benefits in the manufacturing industry the automotive industry, where lead time to market and lean manufacturing are critical to the success of a company. Recent research by the Aberdeen research company found that the most effective manufacturers spend more time simulating upfront and reap the rewards towards the end of their projects. Stamping simulation is used when a sheet metal part designer or toolmaker desires to assess the likelihood of manufacturing a sheet metal part, without the expense of making a physical tool.
Stamping simulation allows any sheet metal part forming process to be simulated in the virtual environment of a PC for a fraction of the expense of a physical tryout. Results from a stamping simulation allow sheet metal part designers to assess alternative designs quickly to optimize their part for low cost manufacture. While the concept of stamping sheet metal components has traditionally focused on the macro level (e.g. vehicle and packag
Glock Ges.m.b. H. is a weapons manufacturer headquartered in Deutsch-Wagram, named after its founder, Gaston Glock. While the company is best known for its line of polymer-framed pistols, it produces field knives, entrenching tools, apparel. Glock handguns are used by armed forces and law enforcement organizations worldwide, including a majority of law enforcement agencies in the United States. In some countries Glock handguns are popular with citizens for personal protection and practical shooting; the company sponsors a competitive shooting team. As of 2014, Glock produces more than two dozen models of handguns in three different sizes and seven different cartridges in three calibers. Glock handguns are common sidearms among law enforcement agencies and military organizations around the world, are largely popular weapons amongst civilians for home defense, concealed/open carry; the popularity of Glock pistols can be attributed to a number of factors. They are reputed as reliable, being able to function under extreme conditions and to fire a wide range of ammunition types.
The simplicity of the Glock design as well as its simple operating method contributes to this reliability, as it contains a small number of components making maintenance and repair easier. The polymer frame makes them lighter than typical steel or aluminum-framed handguns, an attractive feature for police officers and regular citizens who carry firearms for extended periods of time; the trigger is the only operating element. Glock pistols have no other manual safeties; this adds to the simplicity of use and removes a potential source of error while operating the handgun under stress. Most of the steel components in a Glock pistol are treated with a nitriding process called "Tenifer", which increases the surface hardness and makes the pistol resistant to corrosion and wear. Though the Heckler & Koch VP70 was the first polymer-framed pistol and predates the Glock 17 by 12 years, the popularity of Glock pistols inspired other manufacturers to begin production of similar polymer-framed firearms, including the Walther P99, Smith & Wesson Sigma, HS2000, Steyr M, Taurus PT 24/7, Caracal, FN Herstal FNP and Ruger SR9 pistols.
In addition to their semi-automatic handguns, Glock produces a select-fire pistol, the Glock 18, able to be fired in either semi-automatic or automatic mode. This model is available only to law enforcement or military organizations and the details of its production are classified. Conversion kits for other Glocks to be fired in automatic mode exist, but they are third-party, they are marked as Title 2 devices by the U. S. Bureau of Alcohol, Tobacco and Explosives – restricting their purchase and possession to ATF 3 license Dealers in the US. Glock manufactures two models of knives, the Feldmesser 78 and the Feldmesser 81; the Field Knife 78 is a classic type knife, with 290 mm overall length. The Survival Knife 81 has the same overall dimensions with an additional saw on the back of the blade; the Field Knife 78 weighs 206 g and the Survival Knife 81 weighs 202 g. The grips and sheaths are made of polymer and are available in three colors: olive drab and black; as of 2016 Glock introduced a new grey color variant of Field Knife 81 and has plans to discontinue Field Knife 78 in other colors than black.
Glock produces an entrenching tool, the Feldspaten. The Feldspaten features a hardened metal spade blade that can be locked in 3 positions for digging and chopping, a telescopic handle made out of fiberglass-reinforced nylon containing a 175 mm long hardened metal sawblade; the entrenching tool weighs 650 g and extended is 630 mm long. The spade and handle can be collapsed and shortened for easy transport and storage into a 260 mm × 150 mm × 60 mm package; the entrenching tool is supplied with a nylon storage/transport pouch that can be attached to a belt or backpack. Glock current international subsidiaries are: Glock America N. V. Glock, Inc. Glock Ltd. Glock Middle East FZE Glock do Brasil S. A. Glock has been the target of multiple embezzlement schemes involving high-ranking officers of the company or others related to the company. In 1999, Charles Ewert attempted to murder Gaston Glock after Glock asked for a meeting regarding an accusation of embezzlement. Ewert was convicted of attempted murder along with an accomplice for his involvement.
In April 2012, Paul Jannuzzo, the former CEO of US subsidiary Glock, Inc. was convicted of racketeering regarding his involvement in an embezzlement scheme against the company. Investigation of these cases brought to light questionable financial dealings in the background and complicated ownership structure hidden behind a string of shell companies in favourable tax locations around the world. 4825.744-4 893546 Boatman, Robert H. Living With Glocks: The Complete Guide to the New Standard in Combat Handguns. Paladin Press, Boulder. 2002. ISBN 1-58160-340-1. Kasler, Peter Alan. Glock: The N
Piezoelectricity is the electric charge that accumulates in certain solid materials in response to applied mechanical stress. The word piezoelectricity means electricity resulting from latent heat, it is derived from the Greek word πιέζειν. French physicists Jacques and Pierre Curie discovered piezoelectricity in 1880; the piezoelectric effect results from the linear electromechanical interaction between the mechanical and electrical states in crystalline materials with no inversion symmetry. The piezoelectric effect is a reversible process: materials exhibiting the piezoelectric effect exhibit the reverse piezoelectric effect, the internal generation of a mechanical strain resulting from an applied electrical field. For example, lead zirconate titanate crystals will generate measurable piezoelectricity when their static structure is deformed by about 0.1% of the original dimension. Conversely, those same crystals will change about 0.1% of their static dimension when an external electric field is applied to the material.
The inverse piezoelectric effect is used in the production of ultrasonic sound waves. Piezoelectricity is exploited in a number of useful applications, such as the production and detection of sound, piezoelectric inkjet printing, generation of high voltages, electronic frequency generation, microbalances, to drive an ultrasonic nozzle, ultrafine focusing of optical assemblies, it forms the basis for a number of scientific instrumental techniques with atomic resolution, the scanning probe microscopies, such as STM, AFM, MTA, SNOM. It finds everyday uses such as acting as the ignition source for cigarette lighters, push-start propane barbecues, used as the time reference source in quartz watches, in amplification pickups for some guitars; the pyroelectric effect, by which a material generates an electric potential in response to a temperature change, was studied by Carl Linnaeus and Franz Aepinus in the mid-18th century. Drawing on this knowledge, both René Just Haüy and Antoine César Becquerel posited a relationship between mechanical stress and electric charge.
The first demonstration of the direct piezoelectric effect was in 1880 by the brothers Pierre Curie and Jacques Curie. They combined their knowledge of pyroelectricity with their understanding of the underlying crystal structures that gave rise to pyroelectricity to predict crystal behavior, demonstrated the effect using crystals of tourmaline, topaz, cane sugar, Rochelle salt. Quartz and Rochelle salt exhibited the most piezoelectricity; the Curies, did not predict the converse piezoelectric effect. The converse effect was mathematically deduced from fundamental thermodynamic principles by Gabriel Lippmann in 1881; the Curies confirmed the existence of the converse effect, went on to obtain quantitative proof of the complete reversibility of electro-elasto-mechanical deformations in piezoelectric crystals. For the next few decades, piezoelectricity remained something of a laboratory curiosity. More work was done to define the crystal structures that exhibited piezoelectricity; this culminated in 1910 with the publication of Woldemar Voigt's Lehrbuch der Kristallphysik, which described the 20 natural crystal classes capable of piezoelectricity, rigorously defined the piezoelectric constants using tensor analysis.
The first practical application for piezoelectric devices was sonar, first developed during World War I. In France in 1917, Paul Langevin and his coworkers developed an ultrasonic submarine detector; the detector consisted of a transducer, made of thin quartz crystals glued between two steel plates, a hydrophone to detect the returned echo. By emitting a high-frequency pulse from the transducer, measuring the amount of time it takes to hear an echo from the sound waves bouncing off an object, one can calculate the distance to that object; the use of piezoelectricity in sonar, the success of that project, created intense development interest in piezoelectric devices. Over the next few decades, new piezoelectric materials and new applications for those materials were explored and developed. Piezoelectric devices found homes in many fields. Ceramic phonograph cartridges simplified player design, were cheap and accurate, made record players cheaper to maintain and easier to build; the development of the ultrasonic transducer allowed for easy measurement of viscosity and elasticity in fluids and solids, resulting in huge advances in materials research.
Ultrasonic time-domain reflectometers could find flaws inside cast metal and stone objects, improving structural safety. During World War II, independent research groups in the United States and Japan discovered a new class of synthetic materials, called ferroelectrics, which exhibited piezoelectric constants many times higher than natural materials; this led to intense research to develop barium titanate and lead zirconate titanate materials with specific properties for particular applications. One significant example of the use of piezoelectric crystals was developed by Bell Telephone Laboratories. Following World War I, Frederick R. Lack, working in radio telephony in the engineering department, developed the “AT cut” crystal, a crystal that operated through a wide range of temperatures. Lack's crystal didn't nee
A cartridge is a type of pre-assembled firearm ammunition packaging a projectile, a propellant substance and an ignition device within a metallic, paper or plastic case, made to fit within the barrel chamber of a breechloading gun, for the practical purpose of convenient transportation and handling during shooting. Although in popular usage the term "bullet" is used to refer to a complete cartridge, it is used only to refer to the projectile. Cartridges can be categorized by the type of their primers — a small charge of an impact- or electric-sensitive chemical mixture, located at the center of the case head, inside the rim of the case base, in a sideway projection, shaped like a pin or a lip, or in a small nipple-like bulge at the case base. Military and commercial producers continue to pursue the goal of caseless ammunition; some artillery ammunition uses the same cartridge concept. In other cases, the artillery shell is separate from the propellant charge. A cartridge without a projectile is called a blank.
One, inert is called a dummy. One that failed to ignite and shoot off the projectile is called a dud, one that ignited but failed to sufficiently push the projectile out of the barrel is called a squib; the primary purpose is to be a handy all-in-one for a shot. In modern, automatic weapons, it provides the energy to move the parts of the gun which make it fire repeatedly. Many weapons were designed to make use of a available cartridge, or a new one with new qualities; the cartridge case seals a firing chamber in all directions excepting the bore. A firing pin ignites it; the primer compound deflagrates, it does not detonate. A jet of burning gas from the primer ignites the propellant. Gases from the burning powder expand the case to seal it against the chamber wall; these propellant gases push on the bullet base. In response to this pressure, the bullet will move in the path of least resistance, down the bore of the barrel. After the bullet leaves the barrel, the chamber pressure drops to atmospheric pressure.
The case, elastically expanded by chamber pressure, contracts slightly. This eases removal of the case from the chamber. To manufacture brass for cartidges, a sheet of brass is punched into disks; these disks go through a series of punches and dies and are annealed and washed before moving to the next series of dies. Making bullets involves simular type of maching as for making brass cases; the projectile can be made of anything. Lead is a material of choice because of high density, ductility; the propellant was long gunpowder, still in use, but superseded by better compositions, generically called Smokeless powder. Early primer was fine gunpowder poured into a pan or tube where it could be ignited by some external source of ignition such as a fuse or a spark. Modern primers are shock sensitive chemicals enclosed in a small capsule, ignited by percussion. In some instance ignition is electricity-primed, there may be no primer at all in such design; the case is made of brass because it is resistant to corrosion.
A brass case head can be work-hardened to withstand the high pressures of cartridges, allow for manipulation via extraction and ejection without tearing the metal. The neck and body portion of a brass case is annealed to make the case ductile enough to allow reforming so that it can be reloaded many times. Steel is used in some plinking ammunition, as well as in some military ammunition. Steel is less expensive than brass. Military forces consider small arms cartridge cases to be disposable, one-time-use devices. However, case weight affects how much ammunition a soldier can carry, so the lighter steel cases do have a military advantage. Conversely, steel is more susceptible to contamination and damage so all such cases are varnished or otherwise sealed against the elements. One downside caused by the increased strength of steel in the neck of these cases is that propellant gas can blow back past the neck and into the chamber. Constituents of these gases condense on the chamber wall; this solid propellant residue can make extraction of fired cases difficult.
This is less of a problem for small arms of the former Warsaw Pact nations, which were designed with much larger chamber tolerances than NATO weapons. Aluminum cased; these are not reloaded as aluminum fatigues during firing and resizing. Some calibers have non-standard primer sizes to discourage reloaders from attempting to reuse these cases. Plastic cases are used in shotgun shells and some manufacturers offer polymer centerfire cartridges. Paper had been used in the earliest cartridges. Critical cartridge specifications include neck size, bullet weight and caliber, maximum pressure, overall length, case body diameter and taper, shoulder design, rim type, etc. Ever
In destructive testing tests are carried out to the specimen's failure, in order to understand a specimen's performance or material behaviour under different loads. These tests are much easier to carry out, yield more information, are easier to interpret than nondestructive testing. Destructive testing is most suitable, economic, for objects which will be mass-produced, as the cost of destroying a small number of specimens is negligible, it is not economical to do destructive testing where only one or few items are to be produced. Analyzing and documenting the destructive failure mode is accomplished using a high-speed camera recording continuously until the failure is detected. Detecting the failure can be accomplished using a sound detector or stress gauge which produces a signal to trigger the high-speed camera; these high-speed cameras have advanced recording modes to capture any type of destructive failure. After the failure the high-speed camera will stop recording; the capture images can be played back in slow motion showing what happen before and after the destructive event, image by image.
Building structures or large nonbuilding structures are subjected to destructive testing due to the prohibitive cost of constructing a building, or a scale model of a building, just to destroy it. Earthquake engineering requires a good understanding of. Destructive tests are more carried out for structures which are to be constructed in earthquake zones; such tests are sometimes referred to as crash tests, they are carried out to verify the designed seismic performance of a new building, or the actual performance of an existing building. The tests are carried out on a platform called a shake-table, designed to shake in the same manner as an earthquake. Results of those tests include the corresponding shake-table videos. Testing of structures in earthquakes is done by modelling the structure using specialist finite element software. Destructive software testing is a type of software testing which attempts to cause a piece of software to fail in an uncontrolled manner, in order to test its robustness.
Automobiles are subject to crash testing by a variety of agencies. There has been extensive destructive testing of passenger and military aircraft, conducted by aircraft manufacturers and organizations like NASA; the 2012 Boeing 727 crash experiment was filmed by the Discovery channel. Crash test Hardness tests Median lethal dose Metallographic test Nondestructive testing Reproducibility Show and Display Stress tests Testability
A revolver is a repeating handgun that has a revolving cylinder containing multiple chambers and at least one barrel for firing. The revolver allows the user to fire multiple rounds without reloading after every shot, unlike older single shot firearms. After a round is fired the hammer is cocked and the next chamber in the cylinder is aligned with the barrel by the shooter either manually pulling the hammer back or by rearward movement of the trigger. Revolvers still remain popular as back-up and off-duty handguns among American law enforcement officers and security guards and are still common in the American private sector as defensive and sporting/hunting firearms. Famous and iconic revolvers models include the Colt 1851 Navy Revolver, the Webley, the Colt Single Action Army, the Colt Official Police, Smith & Wesson Model 10, the Smith and Wesson Model 29 of Dirty Harry fame, the Nagant M1895. Though revolvers are referred to as and are handguns, other firearms may have a revolver action.
These include some models of grenade launchers, shotguns and cannons, such as revolver cannon. These are different from other firearms with revolving chambers, such as Gatling-style rotary cannons in that revolvers require the hammer to be re-cocked with each shot and require manual reloading, while guns like the minigun are motor driven and have a barrel for each chamber. In the development of firearms, an important limiting factor was the time it took to reload the weapon after it was fired. While the user was reloading, the weapon was useless, an adversary might be able to take advantage of the situation and kill or wound the user. Several approaches to the problem of increasing the rate of fire were developed, the earliest being multi-barrelled weapons which allowed two or more shots without reloading. Weapons featured multiple barrels revolving along a single axis. During the late 16th century in China, Zhao Shi-zhen invented the Xun Lei Chong, a five-barreled musket revolver spear. Around the same time, the earliest examples of what today is called a revolver were made in Germany.
These weapons featured a single barrel with a revolving cylinder holding the ball. They would soon be made in numerous designs and configurations. However, these weapons were difficult to use and prohibitively expensive to make, as such they were not distributed. In 1836, an American, Samuel Colt, patented the mechanism which led to the widespread use of the revolver, the mechanically indexing cylinder. According to Samuel Colt, he came up with the idea for the revolver while at sea, inspired by the capstan, which had a ratchet and pawl mechanism on it, a version of, used in his guns to rotate the cylinder by cocking the hammer; this provided a reliable and repeatable way to index each round and did away with the need to manually rotate the cylinder. Revolvers proliferated due to Colt's ability as a salesman, but his influence spread in other ways as well. Early revolvers were caplocks and loaded as a muzzle-loader: the user poured black powder into each chamber, rammed down a bullet on top of it placed percussion caps on the nipple at the rear of each chamber, where the hammer would fall on it.
This was similar to loading a traditional single-shot muzzle-loading pistol, except that the powder and shot could be loaded directly into the front of the cylinder rather than having to be loaded down the whole length of the barrel. This allowed the barrel itself to be rifled, since the user wasn't required to force the tight fitting bullet down the barrel in order to load it; when firing the next shot, the user would raise his pistol vertically as he cocked the hammer back so as to let the fragments of the burst percussion cap fall out so as to not jam the mechanism. Some of the most popular cap-and-ball revolvers were the Colt Model 1851 "Navy" Model, 1860 "Army" Model, Colt Pocket Percussion revolvers, all of which saw extensive use in the American Civil War. Although American revolvers were the most common, European arms makers were making numerous revolvers by that time as well, many of which found their way into the hands of the American forces, including the single action Lefaucheux and LeMat revolver and the Beaumont–Adams and Tranter revolvers, which were early double-action weapons, in spite of being muzzle-loaders.
In 1854, Eugene Lefaucheux introduced the Lefaucheux Model 1854, the first revolver to use self-contained metallic cartridges rather than loose powder, pistol ball, percussion caps. It is a pinfire revolver holding six rounds. On November 17, 1856, Daniel B. Wesson and Horace Smith signed an agreement for the exclusive use of the Rollin White Patent at a rate of 25 cents for every revolver. Smith & Wesson began production late in 1857 and enjoyed years of exclusive production of rear-loading cartridge revolvers in America, due to their association with Rollin White, who held the patent and vigorously defended it against any perceived infringement by other manufacturers. Although White held the patent, other manufacturers were able to sell firearms using the design, provided they were willing to pay royalties. After White's patent expired in April 1869, a 3rd extension was refused. Other gun-makers wer