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Bench Rest
Benchrest shooting is a shooting sport discipline in which high-precision rifles are rested on a table or bench — rather than being carried in the shooter's hands — while shooting at paper or steel targets, hence the name "benchrest". Both the forearm and buttstock of such a rifle are usually fully supported by bean bags, a bipod/monopod (front/rear) combination, and/or a specially designed fixture device called shooting rest (which may be one- or two-piece depending on competition rules), so that the gun can remain stably pointing at the target without needing to be held by someone. When shooting, the shooter simply sits/stands comfortably behind the table/bench, operates the action and pulls the trigger, without needing to worry about carrying any weight of the gun. This is in contrast to other shooting disciplines, where the shooter has to bear at least part of the gun's weight while holding it steady to aim, even when using support devices such as bipods, tripods or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Action (firearms)
In firearms terminology, an action is the functional mechanism of a breech-loading firearm that handles (loads, locks, fires, extracts and ejects) the ammunition cartridges, or the method by which that mechanism works. Actions are technically not present on muzzleloaders, as all those are single-shot firearms with a closed off breech with the powder and projectile manually loaded from the muzzle. Instead, the muzzleloader ignition mechanism is referred to as the ''lock'' (e.g. matchlock, flintlock, caplock). Actions can be categorized in several ways, including single action versus double action, break action versus bolt action, and others. The term action can also include short, long, and magnum if it is in reference to the length of the rifle's receiver and the length of the bolt. The short action rifle usually can accommodate a cartridge length of or smaller. The long action rifle can accommodate a cartridge of , and the magnum action rifle can accommodate cartrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rimfire Ammunition
Rimfire ammunition is a type of firearm metallic cartridge whose primer is located within a hollow circumferential rim protruding from the base of its casing. When fired, the gun's firing pin will strike and crush the rim against the edge of the barrel breech, sparking the primer compound within the rim, and in turn ignite the propellant within the case. Invented in 1845, by Louis-Nicolas Flobert, the first rimfire metallic cartridge was the .22 BB Cap (a.k.a. 6mm Flobert) cartridge, which consisted of a percussion cap with a bullet attached to the top. While many other different cartridge priming methods have been tried since the 19th century, only rimfire and the later centerfire cartridges survive to the present day with regular usages. The .22 Long Rifle rimfire cartridge, introduced in 1887, is by far the most common ammunition in the world today in terms of units sold. Characteristics Rimfire ammunition is so named because the firing pin strikes and crushes the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handloading
Handloading, or reloading, is the practice of making firearm cartridges by assembling the individual components (case, primer, propellant, and projectile), rather than purchasing mass-assembled, factory-loaded ammunition. The term ''handloading'' is the more general term, and refers generically to the manual assembly of ammunition. ''Reloading'' refers more specifically to handloading using previously fired cases and shells. The terms are often used interchangeably however, as the techniques are largely the same, whether the handloader is using new or recycled components. The differences lie in the initial preparation of cases and shells; new components are generally ready to load, while previously fired components often need additional procedures, such as cleaning, removal of expended primers, or the reshaping and resizing of brass cases. Reasons for handloading Economy, increased performance and accuracy, commercial ammunition shortages, and hobby interests are all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centerfire Ammunition
Two rounds of .357 Magnum, a centerfire cartridge; notice the circular primer in the center A centerfire cartridge is a firearm metallic cartridge whose primer is located at the center of the base of its casing (i.e. "case head"). Unlike rimfire cartridges, the centerfire primer is typically a separate component seated into a recessed cavity (known as the ''primer pocket'') in the case head and is replaceable by reloading. Centerfire cartridges have supplanted the rimfire variety in all but the smallest cartridge sizes. The majority of today's handguns, rifles, and shotguns use centerfire ammunition, with the exception of a few .17 caliber, .20 caliber, and .22 caliber handgun and rifle cartridges, small-bore shotgun shells (intended for pest control), and a handful of antique (and mostly obsolete) cartridges. History An early form of centerfire ammunition, without a percussion cap, was invented between 1808 and 1812 by Jean Samuel Pauly. This was also the first fully i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gunsmithing
A gunsmith is a person who repairs, modifies, designs, or builds guns. The occupation differs from an armorer, who usually replaces only worn parts in standard firearms. Gunsmiths do modifications and changes to a firearm that may require a very high level of craftsmanship, requiring the skills of a top-level machinist, a very skilled woodworker, and even an engineer. Gunsmiths perform factory-level repairs and renovations to restore a well-used or deteriorated firearms to new condition. They may make alterations to adapt sporting guns to better fit the individual shooter that may require extensive modifications to the firearm's stocks and metal parts. Repairs and redesigns may require fabrication and fitting of unavailable parts and assemblies constructed by smiths themselves. Gunsmiths may also renew metal finishes or apply decorative carvings or engravings to guns. Many gun shops offer gunsmithing service on the premises. Overview Gunsmiths may be employed in: *factories by fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Confound
In statistics, a confounder (also confounding variable, confounding factor, extraneous determinant or lurking variable) is a variable that influences both the dependent variable and independent variable, causing a spurious association. Confounding is a causal concept, and as such, cannot be described in terms of correlations or associations.Pearl, J., (2009). Simpson's Paradox, Confounding, and Collapsibility In ''Causality: Models, Reasoning and Inference'' (2nd ed.). New York : Cambridge University Press. The existence of confounders is an important quantitative explanation why correlation does not imply causation. Confounds are threats to internal validity. Definition Confounding is defined in terms of the data generating model. Let ''X'' be some independent variable, and ''Y'' some dependent variable. To estimate the effect of ''X'' on ''Y'', the statistician must suppress the effects of extraneous variables that influence both ''X'' and ''Y''. We say that ''X'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Error
Human error refers to something having been done that was " not intended by the actor; not desired by a set of rules or an external observer; or that led the task or system outside its acceptable limits".Senders, J.W. and Moray, N.P. (1991) Human Error: Cause, Prediction, and Reduction'. Lawrence Erlbaum Associates, p.25. . Human error has been cited as a primary cause contributing factor in disasters and accidents in industries as diverse as nuclear power (e.g., the Three Mile Island accident), aviation (see pilot error), space exploration (e.g., the Space Shuttle Challenger disaster and Space Shuttle Columbia disaster), and medicine (see medical error). Prevention of human error is generally seen as a major contributor to reliability and safety of (complex) systems. Human error is one of the many contributing causes of risk events. Definition Human error refers to something having been done that was "not intended by the actor; not desired by a set of rules or an external observer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muzzleloader
A muzzleloader is any firearm into which the projectile and the propellant charge is loaded from the muzzle of the gun (i.e., from the forward, open end of the gun's barrel). This is distinct from the modern (higher tech and harder to make) designs of breech-loading firearms. The term "muzzleloader" applies to both rifled and smoothbore type muzzleloaders, and may also refer to the marksman who specializes in the shooting of such firearms. The firing methods, paraphernalia and mechanism further divide both categories as do caliber (from cannons to small-caliber palm guns). Modern muzzleloading firearms range from reproductions of sidelock, flintlock and percussion long guns, to in-line rifles that use modern inventions such as a closed breech, sealed primer and fast rifling to allow for considerable accuracy at long ranges. Modern mortars use a shell with the propelling charge and primer attached at the base. Unlike older muzzleloading mortars, which were loaded the same way as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shotgun
A shotgun (also known as a scattergun, or historically as a fowling piece) is a long gun, long-barreled firearm designed to shoot a straight-walled cartridge (firearms), cartridge known as a shotshell, which usually discharges numerous small pellets (petrology), pellet-like spherical sub-projectiles called shot (pellet), shot, or sometimes a single solid projectile called a shotgun slug, slug. Shotguns are most commonly smoothbore firearms, meaning that their gun barrels have no rifling on the inner wall, but rifled barrels for shooting slugs (slug barrels) are also available. Shotguns come in a wide variety of calibers and Gauge (firearms), gauges ranging from 5.5 mm (.22 inch) to up to , though the 12-gauge (18.53 mm or 0.729 in) and 20-gauge (15.63 mm or 0.615 in) bores are by far the most common. Almost all are breechloading, and can be single-barreled, double barreled shotgun, double-barreled, or in the form of a combination gun. Like rifles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handgun
A handgun is a short- barrelled gun, typically a firearm, that is designed to be usable with only one hand. It is distinguished from a long gun (i.e. rifle, shotgun or machine gun, etc.), which needs to be held by both hands and also braced against the shoulder to be used properly. The two most common types of handguns in modern times are revolvers and semi-automatic pistols, although other types such as derringers and machine pistols also see infrequent usage. Before commercial mass production, handguns were often considered a badge of office, comparable to a ceremonial sword. As they had limited utility and were more expensive than the long guns of the era, the few who could only afford to purchase them carried these handguns. However, in 1836, Samuel Colt patented the Colt Paterson, the first practical mass-produced revolver, which was capable of firing five shots in rapid succession and very quickly became a popular defensive weapon, giving rise to the saying, "God cre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sighting In
In ranged weapons such as firearms and artillery pieces, sighting in or sight-in is a preparatory or corrective calibration of the sights with the goal that the projectile (e.g. bullet or shell) may be placed at a predictable impact position within the sight picture. The principle of sighting-in is to shift the line of aim until it intersects the parabolic projectile trajectory at a designated point of reference, so when the gun is fired in the future (provided there is reliable precision) it will repeatably hit where it aims at identical distances of that designated point. Because when using a telescopic sight, the crosshair lines geometrically resemble the X- and Y-axis of the Cartesian coordinate system where the reticle center is analogous to the origin point ( i.e. coordinate ,0, the designated sighting-in point is known as a zero, and the act of sighting-in is therefore also called zeroing. A gunsight that remains true to its designated zero after repeated usage i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
