9781879356511 - Wind Drift and Deceleration of the Cast Bullet at Black-Powder Velocities von Paul A. Matthews (3 Ergebnisse)

Paperback. Zustand: Brand New. 40 pages. 0.40x6.10x9.30 inches. In Stock.

Paperback. Zustand: Brand New. 40 pages. 0.40x6.10x9.30 inches. In Stock.

Wraps. Zustand: Very good. Presumed First Edition, First printing. vii, [1], 39, [1] pages. Includes Introduction to Wind Drift and Deceleration. Also includes chapters on A Closer Look at Wind; Surface Area Versus Wind Drift and Deceleration; Muzzle Velocity Versus Wind Drift and Deceleration; Inertia and Momentum Versus Wind Drift and Deceleration; Bullet Shape Versus Wind Drift and Deceleration; and Summation of Factors Involving Wind Drift and Deceleration. The author left the Navy after WWII and worked at Ingersoll-Rand Company, eventually joining the Technical Publications Department. There he served as a technical writer and eventually as manager of technical publications. During his spare time, he wrote articles about guns and hunting, two or three novels and embarked on a 3-year Famous Writer's Course. He wrote several articles for Gun Digest and other gun publications, as well as a series of fiction hunting stories for both Shooting Times and the Pennsylvania Game News. Since retirement in 1982, he has written several small books relative to rifle shooting published by Wolfe Publishing Company, and one published by Exchange Publishers, Inc. In 1992 at age 66, he became involved in black powder cartridge silhouette competition where I participated in 188 matches, setting four new national records and becoming a co-holder on two other national records. Some of the conclusions the author has reached relative to wind drift and deceleration are in contradiction to our present concept of ballistic coefficient. However, the author believes that his own conclusions are far more correct as they are borne out in actual practice rather than mathematical theory. 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. Wind has a range of effects, the first being the effect of making the projectile deviate to the side (horizontal deflection). From a scientific perspective, the "wind pushing on the side of the projectile" is not what causes horizontal wind drift. What causes wind drift is drag. Drag makes the projectile turn into the wind, much like a weather vane, keeping the center of air pressure on its nose. This causes the nose to be cocked (from your perspective) into the wind, the base is cocked (from your perspective) "downwind." So, (again from your perspective), the drag is pushing the projectile downwind in a nose to tail direction. Wind also causes aerodynamic jump which is the vertical component of cross wind deflection caused by lateral (wind) impulses activated during free flight of a projectile or at or very near the muzzle leading to dynamic imbalance. The amount of aerodynamic jump is dependent on cross wind speed, the gyroscopic stability of the bullet at the muzzle and if the barrel twist is clockwise or anti-clockwise. Like the wind direction reversing the twist direction will reverse the aerodynamic jump direction. A somewhat less obvious effect is caused by head or tailwinds. A headwind will slightly increase the relative velocity of the projectile, and increase drag and the corresponding drop. A tailwind will reduce the drag and the projectile/bullet drop. In the real world, pure head or tailwinds are rare, since wind is seldomly constant in force and direction and normally interacts with the terrain it is blowing over. This often makes ultra long range shooting in head or tailwind conditions difficult.