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Common rifle cartridges, from the largest .50 BMG to the smallest .22 Long Rifle with a $1 United States dollar bill in the background as a reference point. This is a table of selected pistol/submachine gun and rifle/machine gun cartridges by common name. Data values are the highest found for the cartridge, and might not occur in the same load ...
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]
These formulae produce the projectile velocity at range, drag and trajectories. The modern day commercially published ballistic tables or software computed ballistics tables for small arms, sporting ammunition are exterior ballistic, trajectory tables. [49] [50] [51] The 1870 Bashforth tables were to 2,800 ft/s (853 m/s).
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 ...
Values courtesy of the Hornady Ballistic Calculator [14] For the purposes of this comparison barrel a barrel length of 24 in (610 mm) is used. The .458 Lott is able to attain over 2,300-foot-per-second (700 m/s) with a 500-grain (32 g) jacketed bullet at safe pressure levels from a 23–24-inch (580–610 mm) barrel.
The average ballistic coefficient of the 419 grain (27.15 g) is 0.945 over 3,825 yards (3,500 m). Jamison International stated the G1 BC of this bullet on their websitein 2009 at 0.940. Currently (2024) the average ballistic coefficient of the 419 grain (27.15 g) is stated by CheyTac USA at 0.949 over 3,500 yards (3,200 m). [14]
Higher efficiency can be achieved in longer barrel firearms because they have better volume ratio. However, the efficiency gain is less than corresponding to the volume ratio, because the expansion is not truly adiabatic and burnt gas becomes cold faster because of exchange of heat with the barrel. Large firearms (such as cannons) achieve ...
The recommended optional twist rate is one revolution in 10 in (250 mm). Both SAAMI and Weatherby recommend a freebore of .378 in (9.6 mm). Early .257 Weatherby rifles has a twist rate of 1 revolution in 12 in (300 mm) but all current rifles are manufactured with a twist rate of 1 revolution in 10 in (250 mm).