Heckler & Koch P9
The HK P9 is a semi-automatic pistol from Heckler & Koch in 9×19mm Parabellum and the first to use a variation of H&K's roller delayed blowback system in a pistol format and polygonal rifling now common in H&K designs. Design began around 1965 and production ran between 1969 and 1978. Only 485 single-action P9's were produced and were discontinued in 1970. A traditional double action version, the P9S was manufactured in greater numbers; the P9 is a roller-delayed pistol manufactured from a stamped steel main frame and a polymer trigger guard. The stamped steel slide contains machined internal parts including a polygonally rifled barrel. High-profile fixed sights are fitted with two red rectangles on the rear sight and a white stripe on the drift adjustable front blade sight. Vertical zeroing is accomplished by fitting front sights of a different height; the P9S was adopted by the US Navy for use with a sound suppressor. The sound suppressors of the period were comparatively large and the model shown with the P9S make the pistol's sights unusable so the suppressor was equipped with sights.
The fixed barrel of the P9S allows the pistol to operate reliably with the suppressor attached without requiring the recoil booster. Most long and short recoil designs need to compensate for the added muzzle mass and mechanical movement of a mounted suppressor. A shortened version, the P9K was never put into production. In addition to the standard P9S, a P9S Target model was offered; this model included a taller front sight, a windage and elevation adjustable rear sight, an adjustable trigger over-travel stop, an adjustable trigger that could be adjusted down to as low as a 2.5# pull. The P9S Target model was offered in both 9mm as well as.45 ACP. The P9S trigger operates as a traditional double action. There is a lever on the left side of the pistol grip to both decock a cocked hammer or to manually re-cock it for a single action first shot, a feature first observed on the Sauer 38H. A further function of the decocking lever is to release the slide stop; the hammer is concealed within the slide with a protruding pin at the rear of the slide as a cocking indicator.
The operating spring surrounds the barrel, allowing for a lower bore axis than pistols such as John Browning's M1911 that have the operating spring below the barrel. A manual firing-pin safety is located at the left rear of the slide. Typical to European pistols, the magazine release is heel-mounted; the magazine is single column. Algeria: Algerian police Argentina: Argentine Army. West Germany: GSG9 and State police of Saarland. Greece: EP9S variant. Japan: Used by the Special Armed Police Lebanon: Malaysia: Malaysian Armed Forces and used by Organized Crime Investigation Department, Pasukan Gerakan Khas & VAT 69 Commando in the Royal Malaysia Police. Netherlands: Brigade Speciale Beveiligingsopdrachten. Paraguay Portugal: Guarda Nacional Republicana. Saudi Arabia Spain: Grupo Especial de Operaciones. Sudan United States: U. S. Navy. List of individual weapons of the U. S. Armed Forces Maintenance Manual Remtek HKPRo website HKPro.com on the P9 Modern Firearms on the P9
Recoil is the backward movement of a gun when it is discharged. In technical terms, the recoil momentum acquired by the gun balances the forward momentum of the projectile and exhaust gases, according to Newton's third law, known as conservation of momentum. In hand-held small arms, the recoil momentum is transferred to the ground through the body of the shooter. In order to bring the rearward moving gun to a halt, the momentum acquired by the gun is dissipated by a forward acting counter-recoil force applied to the gun over a period of time after the projectile exits the muzzle. To apply this counter-recoiling force, modern mounted guns may employ recoil buffering comprising springs and hydraulic recoil mechanisms, similar to shock absorbing suspension on automobiles. Early cannons used systems of ropes along with rolling or sliding friction to provide forces to slow the recoiling cannon to a stop. Recoil buffering allows the maximum counter-recoil force to be lowered so that strength limitations of the gun mount are not exceeded.
Gun chamber pressures and projectile acceleration forces are tremendous, on the order of tens of thousands of pounds per square inch and tens of thousands of times the acceleration of gravity, both necessary to launch the projectile at useful velocity during the short travel distance of the barrel. However, the same pressures acting on the base of the projectile are acting on the rear face of the gun chamber, accelerating the gun rearward during firing. Practical weight gun mounts are not strong enough to withstand the maximum forces accelerating the projectile during the short time the projectile is in the barrel only a few milliseconds. To mitigate these large recoil forces, recoil buffering mechanisms spread out the counter-recoiling force over a longer time ten to a hundred times longer than the duration of the forces accelerating the projectile; this results in the required counter-recoiling force being proportionally lower, absorbed by the gun mount. Modern cannons employ muzzle brakes effectively to redirect some of the propellant gasses rearward after projectile exit.
This provides a counter-recoiling force to the barrel, allowing the buffering system and gun mount to be more efficiently designed at lower weight. "Recoilless" guns exist where much of the high pressure gas remaining in the barrel after projectile exit is vented rearward though a nozzle at the back of the chamber, creating a large counter-recoiling force sufficient to eliminate the need for heavy recoil mitigating buffers on the mount. The same physics affecting recoil in mounted guns and cannons applies to hand-held guns. However, the shooter's body assumes the role of gun mount, must dissipate the gun's recoiling momentum over a longer period of time than the bullet travel-time in the barrel, in order not to injure the shooter. Hands and shoulders have considerable strength and elasticity for this purpose, up to certain practical limits. "perceived" recoil limits vary from shooter to shooter, depending on body size, the use of recoil padding, individual pain tolerance, the weight of the firearm, whether recoil buffering systems and muzzle brakes are employed.
For this reason, establishing recoil safety standards for small arms remains challenging, in spite of the straight-forward physics involved. A change in momentum of a mass requires a force; that force, applied to a mass, creates an acceleration, which when applied over time, changes the velocity of a mass. According to Newton's second law, the law of momentum -- changing the velocity of the mass changes its momentum, it is important to understand at this point that velocity is not speed. Velocity is the speed of a mass in a particular direction. In a technical sense, speed is a scalar, a magnitude, velocity is a vector and direction. Newton's third law, known as conservation of momentum, recognizes that changes in the motion of a mass, brought about by the application of forces and accelerations, does not occur in isolation. Furthermore, if all the masses and velocities involved are accounted for, the vector sum and direction, of the momentum of all the bodies involved does not change; this conservation of momentum is why gun recoil occurs in the opposite direction of bullet projection -- the mass times velocity of the projectile in the positive direction equals the mass times velocity of the gun in the negative direction.
In summation, the total momentum of the system equals zero just as it did before the trigger was pulled. From a practical engineering perspective, through the mathematical application of conservation of momentum, it is possible to calculate a first approximation of a gun’s recoil momentum and kinetic energy, properly design recoil buffering systems to safely dissipate that momentum and energy based on estimates of the projectile speed coming out the barrel. To confirm analytical calculations and estimates, once a prototype gun is manufactured, the projectile and gun recoil energy and momentum can be directly measured using a ballistic pendulum and ballistic chronograph. There are two conservation laws at work when a gun is fired: conservation of momentum and conservation of energy. Rec
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
A magazine is an ammunition storage and feeding device within or attached to a repeating firearm. Magazines can be integral to the firearm; the magazine functions by moving the cartridges stored within it into a position where they may be loaded into the barrel chamber by the action of the firearm. The detachable magazine is colloquially referred to as a clip, although this is technically inaccurate. Magazines come in many shapes and sizes, from tubular magazines on lever-action rifles that hold only a few rounds, to detachable box and drum magazines for automatic rifles and machine guns that can hold more than one hundred rounds. Various jurisdictions ban what they define as "high-capacity magazines". With the increased use of semi-automatic and automatic firearms, the detachable magazine became common. Soon after the adoption of the M1911 pistol, the term "magazine" was settled on by the military and firearms experts, though the term "clip" is used in its place; the defining difference between clips and magazines is the presence of a feed mechanism in a magazine a spring-loaded follower, which a clip lacks.
A magazine has four parts as follows. A clip may have no moving parts. Examples of clips are moon clips for revolvers. Use of the term "clip" to refer to detachable magazines is a point of strong disagreement; the earliest firearms were loaded with loose powder and a lead ball, to fire more than a single shot without reloading required multiple barrels, such as pepper-box guns and double-barreled shotguns, or multiple chambers, such as in revolvers. Both of these add bulk and weight over a single barrel and a single chamber and many attempts were made to get multiple shots from a single loading of a single barrel through the use of superposed loads. While some early repeaters such as the Kalthoff repeater managed to operate using complex systems with multiple feed sources for ball and primer mass-produced repeating mechanisms did not appear until self-contained cartridges were developed; the first mass-produced repeater was the Volcanic Rifle which used a hollow bullet with the base filled with powder and primer fed into the chamber from a spring-loaded tube called a magazine.
It was named after a room used to store ammunition. The anemic power of the Rocket Ball ammunition used in the Volcanic doomed it to limited popularity.. The Henry repeating rifle is a lever-action, breech-loading, tubular magazine fed rifle, was an improved version of the earlier Volcanic rifle. Designed by Benjamin Tyler Henry in 1860, it was one of the first firearms to use self-contained metallic cartridges; the Henry was introduced in the early 1860s and produced through 1866 in the United States by the New Haven Arms Company. It was adopted in small quantities by the Union in the Civil War and favored for its greater firepower than the standard issue carbine. Many found their way West and was famed both for its use at the Battle of the Little Bighorn, being the basis for the iconic Winchester rifle which are still made to this day; the Henry and Winchester rifles would go on to see service with a number of militaries including Turkey. Switzerland and Italy adopted similar designs; the first magazine-fed firearm to achieve widespread success was the Spencer repeating rifle, which saw service in the American Civil War.
The Spencer used a tubular magazine located in the butt of the gun instead of under the barrel and it used new rimfire metallic cartridges. The Spencer was successful, but the rimfire ammunition did ignite in the magazine tube and destroy the magazine, it could injure the user. The new bolt-action rifles began to gain favor with militaries in the 1880s and were equipped with tubular magazines; the Mauser Model 1871 was a single-shot action that added a tubular magazine in its 1884 update. The Norwegian Jarmann M1884 was adopted in 1884 and used a tubular magazine; the French Lebel Model 1886 rifle used 8-round tubular magazine. The military cartridge was evolving. Cartridges evolved from large-bore cartridges to smaller bores that fired lighter, higher-velocity bullets and incorporated new smokeless propellants; the Lebel Model 1886 rifle was the first rifle and cartridge to be designed for use with smokeless powder and used an 8 mm wadcutter-shaped bullet, drawn from a tubular magazine. This would become a problem when the Lebel's ammunition was updated to use a more aerodynamic pointed bullet.
Modifications had to be made to the centerfire case to prevent the spitzer point from igniting the primer of the next cartridge inline in the magazine through recoil or rough handling. This remains a concern with lever-action firearms today. Two early box magazine patents were the ones by Rollin White in 1855 and William Harding in 1859. A detachable box magazine was patented in 1864 by the American Robert Wilson. Unlike box magazines this magazine fed into a tube magazine and was located in the stock of the gun. Another box magazine, closer to the modern type, was patented in Britain by Mowbray Walker, George Henry Money and Francis Little in 1867. James Paris Lee patented a box magazine which held rounds stacked vertically in 1879 and 1882 and it was first adopted by Austria in the form of an 11mm straight-pull bolt-action rifle, the Mannlicher M1886, it used a cartridge clip which held 5 rounds ready to load into the ma
A gun barrel is a crucial part of gun-type ranged weapons such as small firearms, artillery pieces and air guns. It is the straight shooting tube made of rigid high-strength metal, through which a contained rapid expansion of high-pressure gas is introduced behind a projectile in order to propel it out of the front end at a high velocity; the hollow interior of the barrel is called the bore. The measurement of the diameter of the bore is called the caliber. Caliber is measured in inches or millimetres; the first firearms were made at a time when metallurgy was not advanced enough to cast tubes capable of withstanding the explosive forces of early cannons, so the pipe needed to be braced periodically along its length for reinforcement, producing an appearance somewhat reminiscent of storage barrels being stacked together, hence the English name. Gun barrels are metal. However, the early Chinese, the inventors of gunpowder, used bamboo, which has a strong tubular stalk and is cheaper to obtain and process, as the first barrels in gunpowder projectile weapons such as the fire lances.
The Chinese were the first to master cast-iron cannon barrels, used the technology to make the earliest infantry firearms — the hand cannons. Early European guns were made of wrought iron with several strengthening bands of the metal wrapped around circular wrought iron rings and welded into a hollow cylinder. Bronze and brass were favoured by gunsmiths because of their ease of casting and their resistance to the corrosive effects of the combustion of gunpowder or salt water when used on naval vessels. Early firearms were muzzle-loading, with the gunpowder and the shot loaded from the front end of the barrel, were capable of only a low rate of fire due to the cumbersome loading process; the later-invented breech-loading designs provided a higher rate of fire, but early breechloaders lacked an effective way of sealing the escaping gases that leaked from the back end of the barrel, reducing the available muzzle velocity. During the 19th century, effective breechblocks were invented that sealed a breechloader against the escape of propellant gases.
Early cannon barrels were thick for their caliber. This was because manufacturing defects such as air bubbles trapped in the metal were common back in the days, played key factors in many gun explosions. A gun barrel must be able to hold in the expanding gas produced by the propellants to ensure that optimum muzzle velocity is attained by the projectile as it is being pushed out. If the barrel material cannot cope with the pressure within the bore, the barrel itself might suffer catastrophic failure and explode, which will not only destroy the gun but present a life-threatening danger to people nearby. Modern small arms barrels are made of carbon steel or stainless steel materials known and tested to withstand the pressures involved. Artillery pieces are made by various techniques providing reliably sufficient strength. In firearms terminology, fluting refers to the removal of material from a cylindrical surface creating rounded grooves, for the purpose of reducing weight; this is most done to the exterior surface of a rifle barrel, though it may be applied to the cylinder of a revolver or the bolt of a bolt-action rifle.
Most flutings on rifle barrels and revolver cylinders are straight, though helical flutings can be seen on rifle bolts and also rifle barrels. While the main purpose of fluting is just to reduce weight and improve portability, when adequately done it can retain the structural strength and rigidity and increase the overall specific strength. Fluting will increase the surface-to-volume ratio and make the barrel more efficient to cool after firing, though the reduced material mass means the barrel will heat up during firing; the chamber is the cavity at the back end of a breech-loading gun's barrel where the cartridge is inserted in position ready to be fired. In most firearms, the chamber is an integral part of the barrel made by reaming the rear bore of a barrel blank, with a single chamber within a single barrel. In revolvers, the chamber is a component of the gun's cylinder and separate from the barrel, with a single cylinder having multiple chambers that are rotated in turns into alignment with the barrel in anticipation of being fired.
Structurally, the chamber consists of the body and neck, the contour of which correspond to the casing shape of the cartridge it is designed to hold. The rear opening of the chamber is the breech of the whole barrel, sealed tight from behind by the bolt, making the front direction the path of least resistance during firing; when the cartridge's primer is struck by the firing pin, the propellant is ignited and deflagrates, generating high-pressure gas expansion within the cartridge case. However, the chamber restrains the cartridge case from moving, allowing the bullet to separate cleanly from the casing and be propelled forward along the barrel to exit out of the front end as a projectile; the act of chambering a gun refers to the process of loading a cartridge into the gun's chamber, either manually as in single loading, or via operating the weapon's own action as in pump action, lever action, bolt action or self-loading actions. In the case of an air gun, a pellet itself has no casing to be retained and will be inserted into the chamber (often called "seating
The Calico M960 is a 9×19mm semi-automatic carbine, manufactured by Calico Light Weapons Systems. Its features include its high-capacity, helical-feed magazine and retractable stock; this method allows magazine capacities of 50 and 100 rounds in a small space. The rear sight is mounted as part of the plastic magazine shell. Official Site Modern Firearms
Danuvia 43M submachine gun
The Danuvia 39M/43M was a Hungarian submachine gun designed by Pál Király in the late 1930s. The 9×25mm Danuvia submachine gun was designed by Hungarian engineer Pál Király in the late 1930s, they were issued to Hungarian army troops in 1939 and remained in service throughout World War II until the early 1950s. A total of 8,000 were made between 1939 and 1945; the Danuvia was a sturdy weapon, similar to a carbine. Although inspired by the 9×19mm Parabellum Beretta Model 38/42, the Danuvia used the more powerful 9×25mm Mauser round; the Danuvia's magazine can be folded forward into a recess in the stock where a plate slides over it. The gun was well-liked by troops; the only difficulty was the availability of 9×25mm Mauser ammunition. It was used by the Hungarian army, military police and police forces and stayed in service until the early 1950s when it was replaced by the PPSh-41 and the Kucher K1; the Danuvia featured a patented two-part lever-delayed blowback bolt. The fire selector switch is a circular cap on the rear of the receiver and is rotated to one of three settings: E, S, or Z.
The ejection port and cocking handle are on the right side of the receiver. It had a ramp-type rear sight above a post foresight at end of the barrel; the original Danuvia was the Géppisztoly 39M with a fixed wooden stock, followed in limited numbers by the Géppisztoly 39M/A with a folding wooden stock. In 1943 a new version with a forward folding metal stock, wood fore stock and a pistol grip was designated the Géppisztoly 43M; the 43M had a shortened barrel and a forward-angled magazine. Kiraly 43M: Hungary's Overpowered Submachine Gun submachine guns Modern Arms Entry