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External Ballistics
External ballistics or exterior ballistics is the part of ballistics that deals with the behavior of a projectile in flight. The projectile may be powered or un-powered, guided or unguided, spin or fin stabilized, flying through an atmosphere or in the vacuum of space, but most certainly flying under the influence of a gravitational field. Gun-launched projectiles may be unpowered, deriving all their velocity from the propellant's ignition until the projectile exits the gun barrel. However, exterior ballistics analysis also deals with the trajectories of rocket-assisted gun-launched projectiles and gun-launched rockets; and rockets that acquire all their trajectory velocity from the interior ballistics of their on-board propulsion system, either a rocket motor or air-breathing engine, both during their boost phase and after motor burnout. External ballistics is also concerned with the free-flight of other projectiles, such as balls, arrows etc. Forces acting on the projectile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullet Wiki
A bullet is a Kinetic energy weapon, kinetic projectile, a component of firearm ammunition that is Shooting, shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constructions (depending on the intended applications), including specialized functions such as hunting, Shooting sports, target shooting, training, and combat. Bullets are often tapered, making them more Aerodynamics, aerodynamic. Bullet size is expressed by weight and diameter (referred to as "caliber") in both imperial and metric measurement systems. Bullets do not normally contain explosives but strike or damage the intended target by transferring kinetic energy upon impact and Penetration (weaponry), penetration. Description The term ''bullet'' is from Early French, originating as the diminutive of the word ''boulle'' (''boullet''), which means "small ball". Bullets are available singly (as in Muzzleloader, muzz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large-calibre Artillery
The formal definition of large-calibre artillery used by the United Nations Register of Conventional Arms (UNROCA) is "field gun, guns, howitzers, artillery pieces, combining the characteristics of a field gun, gun, howitzer, mortar (weapon), mortar, or multiple rocket launcher, rocket, capable of engaging surface targets by delivering primarily indirect fire, with a Caliber, calibre of and above". This definition, shared by the Arms Trade Treaty and the Treaty on Conventional Armed Forces in Europe, is updated from an earlier definition in United Nations General Assembly Resolution 46/36L, which set a threshold of . Several grammatical changes were made to that latter in 1992 and the threshold was lowered in 2003 to yield the current definition, as endorsed by UN General Assembly Resolution 58/54. Historically, large-calibre weapons have included bombard (weapon), bombards and siege guns. Late Middle Ages In the context of Late Middle Ages, late medieval siege warfare the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematical Model
A mathematical model is an abstract and concrete, abstract description of a concrete system using mathematics, mathematical concepts and language of mathematics, language. The process of developing a mathematical model is termed ''mathematical modeling''. Mathematical models are used in applied mathematics and in the natural sciences (such as physics, biology, earth science, chemistry) and engineering disciplines (such as computer science, electrical engineering), as well as in non-physical systems such as the social sciences (such as economics, psychology, sociology, political science). It can also be taught as a subject in its own right. The use of mathematical models to solve problems in business or military operations is a large part of the field of operations research. Mathematical models are also used in music, linguistics, and philosophy (for example, intensively in analytic philosophy). A model may help to explain a system and to study the effects of different components, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photography Of Bow Shock Waves Around A Brass Bullet, 1888
Photography is the art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication. A person who operates a camera to capture or take photographs is called a photographer, while the captured image, also known as a photograph, is the result produced by the camera. Typically, a lens is used to focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed exposure. With an electronic image sensor, this produces an electrical charge at each pixel, which is electronically processed and stored in a digital image file for subsequent display or processing. The res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Point-blank Range
Point-blank range is any distance over which a certain firearm or gun can hit a target without the need to elevate the barrel to compensate for bullet drop, i.e. the gun can be pointed horizontally at the target. For targets beyond-blank range, the shooter will have to point the barrel of their firearm at a position above the target, and firearms that are designed for long range firefights usually have adjustable sights to help the shooter hit targets beyond point-blank range. The maximum point-blank range of a firearm will depend on a variety of factors such as muzzle velocity and the size of the target. In popular usage, point-blank range has come to mean extremely close range with a firearm, yet not close enough to be a contact shot. Point-blank (when describing a person) means direct or blunt. History The term ''point-blank'' dates to the 1570s and is probably of French origin, deriving from , "pointed at white". It is thought the word ''blanc'' may be used to describe a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Table
A ballistic table or ballistic chart, also known as the data of previous engagements (DOPE) chart, is a reference data chart used in long-range shooting to predict the trajectory of a projectile and compensate for physical effects of gravity and wind drift, in order to increase the probability of the projectile successfully reaching the intended target. Ballistic tables commonly are used in target shooting, hunting, military sharpshooting and ballistic science applications. Ballistic chart data are typically given in angular measurements with units in either milliradians (mil/mrad) or minutes of arc (MOA), arranged in a table format with the rows representing different reference distances and the columns corresponding to categories of information (e.g. angular deviations, actual drop/drift distance, " click" count, etc.) in which the shooter is interested. After ranging the intended target, the shooter can then read off the chart data to estimate the ballistic correction require ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Trajectory
In physics, projectile motion describes the motion of an object that is launched into the air and moves under the influence of gravity alone, with air resistance neglected. In this idealized model, the object follows a parabolic path determined by its initial velocity and the constant acceleration due to gravity. The motion can be decomposed into horizontal and vertical components: the horizontal motion occurs at a constant velocity, while the vertical motion experiences uniform acceleration. This framework, which lies at the heart of classical mechanics, is fundamental to a wide range of applications—from engineering and ballistics to sports science and natural phenomena. Galileo Galilei showed that the trajectory of a given projectile is parabolic, but the path may also be straight in the special case when the object is thrown directly upward or downward. The study of such motions is called ballistics, and such a trajectory is described as ballistic. The only force of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sighting In
In ranged weapons such as firearms and artillery pieces, the act of sighting in or sight-in is a preparatory or corrective calibration of the sights with the goal of having the projectile (e.g. bullet or shell) placed on a predictable impact position in relation to 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Of Mass
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weight function, weighted relative position (vector), position of the distributed mass sums to zero. For a rigid body containing its center of mass, this is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. Calculations in mechanics are often simplified when formulated with respect to the center of mass. It is a hypothetical point where the entire mass of an object may be assumed to be concentrated to visualise its motion. In other words, the center of mass is the particle equivalent of a given object for application of Newton's laws of motion. In the case of a single rigid body, the center of mass is fixed in relation to the body, and if the body has uniform density, it will be located at the centroid. The center of mass may be located outside the Phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Of Pressure (fluid Mechanics)
In fluid mechanics, the center of pressure is the point on a body where a single force acting at that point can represent the total effect of the pressure field acting on the body. The total force vector acting at the center of pressure is the surface integral of the pressure vector field across the surface of the body. The resultant force and center of pressure location produce an equivalent force and moment on the body as the original pressure field. Pressure fields occur in both static and dynamic fluid mechanics. Specification of the center of pressure, the reference point from which the center of pressure is referenced, and the associated force vector allows the moment generated about any point to be computed by a translation from the reference point to the desired new point. It is common for the center of pressure to be located on the body, but in fluid flows it is possible for the pressure field to exert a moment on the body of such magnitude that the center of press ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M829 (munition)
The M829 is an American armor-piercing fin-stabilized discarding sabot ( APFSDS) kinetic energy penetrator tank round. Modeling was done at the Ballistic Research Laboratory at Aberdeen Proving Ground, which was incorporated into the Army Research Laboratory in 1992. The round is specifically designed for the 120 mm M256 main gun on the Abrams M1A1 and M1A2 main battle tanks. The penetrator is carried by a sabot during its acceleration in the gun barrel. Variants M829 The M829 dart has a ballistic nose and six tail fins made of aluminum. It is carried in the gun tube by a four-piece aluminum sabot, which separates into four "petals" soon after the round leaves the gun tube. The propulsion system uses an obturating case base with a semi-combustible cartridge wall. It has a total weight of and a DU penetrator with a rod diameter, which reaches a muzzle velocity of using of JA-2 propellant. Its maximum effective range is . According to Jane's, the M829 is capable of pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
