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Frangible Bullet
Frangible bullets are intended to disintegrate into tiny particles upon target impact to minimize their penetration of other objects. Small particles are slowed more rapidly by air resistance, and are less likely to cause injury or damage to persons and objects distant from the point of bullet impact. Most frangible bullets are subject to brittle failure upon striking a hard target. This mechanism has been used to minimize the tendency of malleable lead and copper bullets to ricochet from hard targets as large, cohesive particles. Brittle failure may occur at subsonic velocity. Attempting to crimp a brittle frangible bullet into the cartridge case may break the bullet. Brittle frangible bullets may break during the self-loading cycle of semi-automatic firearms; and those fired from revolvers often break as the bullet encounters the barrel forcing cone after leaving the cylinder. Manufacturing Powder metallurgy techniques fabricate bullets from mixtures of powdered metals (typic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frangible Bullet Stress Test
A material is said to be frangible if through deformation it tends to break up into fragments, rather than deforming elastically and retaining its cohesion as a single object. Common crackers are examples of frangible materials, while fresh bread, which deforms plastically, is ''not'' frangible. A structure is frangible if it breaks, distorts, or yields on impact so as to present a minimum hazard. A frangible structure is usually designed to be frangible and to be of minimum mass. Light poles A frangible light pole base is designed to break away when a vehicle strikes it. This lessens the risk of injury to occupants of the vehicle. Frangible supports are also used for airport approach structures. Bullets A frangible bullet is one that is designed to disintegrate into tiny particles upon impact to minimize their penetration for reasons of range safety, to limit environmental impact, or to limit the danger behind the intended target. Examples are the Glaser Safety Slug and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sintering
Clinker nodules produced by sintering Sintering or frittage is the process of compacting and forming a solid mass of material by pressure or heat without melting it to the point of liquefaction. Sintering happens as part of a manufacturing process used with metals, ceramics, plastics, and other materials. The atoms in the materials diffuse across the boundaries of the particles, fusing the particles together and creating one solid piece. Because the sintering temperature does not have to reach the melting point of the material, sintering is often chosen as the shaping process for materials with extremely high melting points such as tungsten and molybdenum. The study of sintering in metallurgical powder-related processes is known as powder metallurgy. An example of sintering can be observed when ice cubes in a glass of water adhere to each other, which is driven by the temperature difference between the water and the ice. Examples of pressure-driven sintering are the compact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel Target
Steel targets are shooting targets made out of hardened (martensitic) steel, and are used in firearm and airgun sports such as silhouette shooting, cowboy action shooting, practical/dynamic shooting, long range shooting and field target, as well as recreational plinking. They are popular in both training and competitions because the shooter gets instant acoustic feedback on a successful impact, and can often also visually confirm hits by seeing the bullet getting pulverized, leaving a mark on the surface paint, or moving/knocking down the target. Hanging steel plates (colloquially called "gongs") or self-resetting steel targets also have the advantage that the shooter does not need to go forward downrange to tape the targets, making it a good option for shooting ranges that otherwise have electronic targets. Steel targets also are weatherproof, contrary to paper targets, which do not hold up in rain and wind gusts. Precautions regarding ricochets If correct precautions are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute Of Standards And Technology
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical science laboratory programs that include nanoscale science and technology, engineering, information technology, neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency was named the National Bureau of Standards. History Background The Articles of Confederation, ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of the Constitution of the United States, ratified in 1789, granted these powers to the new Congr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Law Enforcement Standards
An office is a space where an Organization, organization's employees perform Business administration, administrative Work (human activity), work in order to support and realize objects and Goals, plans, action theory, goals of the organization. The word "office" may also denote a position within an organization with specific duties attached to it (see officer (other), officer, office-holder (other), office-holder, official); the latter is in fact an earlier usage, office as place originally referring to the location of one's duty. When used as an adjective, the term "office" may refer to business-related tasks. In legal, law, a company or organization has offices in any place where it has an official presence, even if that presence consists of (for example) a storage silo rather than an establishment with desk-and-office chair, chair. An office is also an architectural and design phenomenon: ranging from a small office such as a Bench (furniture), bench in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
