A very-low-drag bullet (VLD) is primarily a small armsballistics development of the 1980s–1990s, driven by the design objective of bullets with higher degrees of accuracy and kinetic efficiency, especially at extended ranges. To achieve this, the projectile must minimize air resistance in flight. Usage has been greatest from military snipers and long-range target shooters, including F-class and benchrest competitors, but hunters have also benefited. Most VLD bullets are used in rifles. VLD bullets typically have a ballistic coefficient greater than 0.5, although the threshold is undefined.[1]
A traditional hollow point boat tail very-low-drag rifle bullet. The jackets of these bullets are generally made out of a copperalloy (such as gilding metal or cupronickel)
Bullets with a lower drag coefficient decelerate less rapidly. A low drag coefficient flattens the projectile's trajectory and also markedly decreases the lateral drift caused by crosswinds. The higher velocity of bullets with low drag coefficients means they retain more kinetic energy.[1]
VLD bullets are long and heavy for their diameter, to achieve a high sectional density.[1] Development of VLD bullets has focused on reducing a form factor defined as the sectional density divided by the ballistic coefficient.[2] Form factor can be minimized by:
The resulting projectile should be streamlined for easier passage through the air. Consistency in bullet production, allied to consistency in the assembly of cartridges (quality control) should give excellent shot-to-shot consistency.[citation needed]
The principles of bullet design and flight are classically set out in Franklin Ware Mann's The Bullet's Flight From Powder to Target: Ballistics of Small Arms.[4]
Mono-metal designs
Machining mono-metal bullets (coreless bullets made of one single metal) offers bullet designers the freedom to design slender, aerodynamically efficient shapes that cannot be produced with more traditional bullet production methods. Professional quality control during and after production is needed to guarantee the bullets' consistency and accuracy. Mono-metal solid bullets are more expensive than traditional jacketed hollow point boat-tail VLD bullets.[citation needed]
To reduce damage to the employed barrel and increase muzzle velocity, some modern mono-metal VLD bullets are bore-riding bullets, in which thin driving bands are the only parts that are etched by a barrel's lands. The use of driving bands originates from artilleryshells and to use these driving bands correctly requires projectiles and barrels to be precision-fitted to each other.[citation needed]
Mono-metal VLD bullets are normally machined from solid bars of highly-machinable metals or alloys using CNC lathes. Common materials include UNS C36000 free-cutting brass, lead-free brass,[5]oxygen-free copper and other highly machinable alloys of copper, nickel, and tellurium.[citation needed]
very, drag, bullet, very, drag, bullet, primarily, small, arms, ballistics, development, 1980s, 1990s, driven, design, objective, bullets, with, higher, degrees, accuracy, kinetic, efficiency, especially, extended, ranges, achieve, this, projectile, must, mini. A very low drag bullet VLD is primarily a small arms ballistics development of the 1980s 1990s driven by the design objective of bullets with higher degrees of accuracy and kinetic efficiency especially at extended ranges To achieve this the projectile must minimize air resistance in flight Usage has been greatest from military snipers and long range target shooters including F class and benchrest competitors but hunters have also benefited Most VLD bullets are used in rifles VLD bullets typically have a ballistic coefficient greater than 0 5 although the threshold is undefined 1 A traditional hollow point boat tail very low drag rifle bullet The jackets of these bullets are generally made out of a copper alloy such as gilding metal or cupronickel Bullets with a lower drag coefficient decelerate less rapidly A low drag coefficient flattens the projectile s trajectory and also markedly decreases the lateral drift caused by crosswinds The higher velocity of bullets with low drag coefficients means they retain more kinetic energy 1 Contents 1 Development 2 Mono metal designs 3 See also 4 References 5 External linksDevelopment EditVLD bullets are long and heavy for their diameter to achieve a high sectional density 1 Development of VLD bullets has focused on reducing a form factor defined as the sectional density divided by the ballistic coefficient 2 Form factor can be minimized by bullet nose design incorporating a secant ogive tangent ogive Von Karman ogive or Sears Haack profile 3 the use of tapered bullet heels also known as boat tails 1 a cavity or hollow in the bullet nose hollow point to reduce weight while shifting the projectile s centre of gravity rearwards 1 to improve stability with concentric and coincident centre of pressure and centre of mass citation needed The resulting projectile should be streamlined for easier passage through the air Consistency in bullet production allied to consistency in the assembly of cartridges quality control should give excellent shot to shot consistency citation needed The principles of bullet design and flight are classically set out in Franklin Ware Mann s The Bullet s Flight From Powder to Target Ballistics of Small Arms 4 Mono metal designs EditMachining mono metal bullets coreless bullets made of one single metal offers bullet designers the freedom to design slender aerodynamically efficient shapes that cannot be produced with more traditional bullet production methods Professional quality control during and after production is needed to guarantee the bullets consistency and accuracy Mono metal solid bullets are more expensive than traditional jacketed hollow point boat tail VLD bullets citation needed To reduce damage to the employed barrel and increase muzzle velocity some modern mono metal VLD bullets are bore riding bullets in which thin driving bands are the only parts that are etched by a barrel s lands The use of driving bands originates from artillery shells and to use these driving bands correctly requires projectiles and barrels to be precision fitted to each other citation needed Mono metal VLD bullets are normally machined from solid bars of highly machinable metals or alloys using CNC lathes Common materials include UNS C36000 free cutting brass lead free brass 5 oxygen free copper and other highly machinable alloys of copper nickel and tellurium citation needed See also EditDrag physics Parasitic drag Boundary layer Nose cone designReferences Edit a b c d e Petzal David E 7 July 2014 Understanding VLD Bullets Field amp Stream Retrieved 13 June 2018 Litz Bryan Form Factors A Useful analysis Tool PDF Applied Ballistics Retrieved 13 June 2018 Lines And Designs Berger Bullets Retrieved 13 June 2018 Mann F W The Bullet s Flight From Powder to Target Ballistics of Small Arms 1942 and other reprints Wieland SW1 lead free special brass permanent dead link External links EditVLD bullets on long rangevarmint hunting Retrieved from https en wikipedia org w index php title Very low drag bullet amp oldid 1098236506, wikipedia, wiki, book, books, library,
