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Thus the optimum rate of twist for this bullet should be approximately 12 inches per turn. The typical twist of .30-06 caliber rifle barrels is 10 inches per turn, accommodating heavier bullets than in this example. A different twist rate often helps explain why some bullets work better in certain rifles when fired under similar conditions.
The common rifling twist rate for this cartridge is 305 mm (1 in 12 in), 4 grooves, Ø lands = 7.62 mm, ... (100 ft/s)) muzzle velocity with most bullet weights.
The standard bullet diameter for 6 mm caliber cartridges is .243 inches (6.2 mm), the same diameter used in the .243 Winchester and 6mm Remington cartridges. To obtain maximum accuracy, bullet weight and form are matched to the rifling twist rate of the barrel. Typically, 68 gr (4.41 g) bullets are used in barrels with twist rates of 1 in 13 ...
Remington determined that a 90 grain soft point .244 hunting bullet was well suited for medium-sized big game hunting purposes. For the length and weight of its 90 grain soft point hunting bullet, Remington selected a 1 in 12-inch twist. By selecting the slowest twist possible, Remington was seeking to avoid excessive spin.
The streamlined bullet was based on the 7.5×55mm Swiss GP11 projectiles and slightly longer and heavier than the Mk VII bullet at 175 gr (11.34 g), the primary difference was the addition of a boat tail at the end of the bullet and using 37 to 41 gr (2.40 to 2.66 g) of nitrocellulose smokeless powder as propellant in the case of the Mk VIIIz ...
The 160 gr (10 g) bullet which has a sectional density of 0.328 is similar in sectional density to a 220 gr (14 g) .308 caliber (7.62 mm) bullet. As sectional density plays a large factor in penetration, the .264 caliber (6.5 mm), though a diminutive caliber from a North American point of view, has had excellent results in the field.
The 7.92×57mm Mauser can offer very good penetrating ability due to a fast twist rate that enables it to fire long, heavy bullets with a high sectional density. [citation needed] The 7.92×57mm Mauser cannot be used in countries that ban civil use of former or current military rifle cartridges, though since 2013 is no longer restricted in France.
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.