Search results
Results from the WOW.Com Content Network
Miller twist rule is a mathematical formula derived by American physical chemist and historian of science Donald G. Miller (1927-2012) to determine the rate of twist to apply to a given bullet to provide optimum stability using a rifled barrel. [1]
Rifling of a 105 mm Royal Ordnance L7 tank gun Conventional rifling of a 90 mm M75 cannon (production year 1891, Austria-Hungary) Rifling in a GAU-8 autocannon. Rifling is the term for helical grooves machined into the internal surface of a firearms's barrel for imparting a spin to a projectile to improve its aerodynamic stability and accuracy.
Historically, this table has been referred to as a "drop table." The drop table can be generated empirically using data taken by the shooter at a rifle range; calculated using a ballistic simulator; or is provided by the rifle/cartridge manufacturer. The drop values are measured or calculated assuming the rifle has been zeroed at a specific range.
The maximum practical range [note 4] of all small arms and especially high-powered sniper rifles depends mainly on the aerodynamic or ballistic efficiency of the spin stabilised projectiles used. Long-range shooters must also collect relevant information to calculate elevation and windage corrections to be able to achieve first shot strikes at ...
Firearm muzzle velocities range from approximately 120 m/s (390 ft/s) to 370 m/s (1,200 ft/s) in black powder muskets, [3] to more than 1,200 m/s (3,900 ft/s) [4] in modern rifles with high-velocity cartridges such as the .220 Swift and .204 Ruger, all the way to 1,700 m/s (5,600 ft/s) [5] for tank guns firing kinetic energy penetrator ammunition.
According to Newtonian mechanics, if the gun and shooter are at rest initially, the force on the bullet will be equal to that on the gun-shooter. This is due to Newton's third law of motion (For every action, there is an equal and opposite reaction). Consider a system where the gun and shooter have a combined mass m g and the bullet has a mass m b.
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves ("rifling") cut into the barrel walls.The raised areas of the rifling are called "lands," which make contact with the projectile (for small arms usage, called a bullet), imparting spin around an axis corresponding to the orientation of the weapon.
Example of a ballistic table for a given 7.62×51mm NATO load. Bullet drop and wind drift are shown both in mrad and MOA.. 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 ...