Greenhill formula for rifling twist

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August undefined, 2024

WebMar 7, 2024 · Barrel twist rates are determined by using either the Greenhill or Miller formulas.. Generally the lighter the bullet for a given barrel the slower the twist. Velocity is not part of the equation.. Best examples l can think of to illustrate this principle is 223Rem. When first introduced most barrels had a 1 in 12 twist for a 55gr bullet. WebMay 8, 2004 · According to Greenhill's formula, then, the proper rate of twist for the Sierra .30-caliber, 200-gr MatchKing is 1:10". That said, and with all due respect to Greenhill, some long-range [smokeless powder] shooters are experimenting with slower rates of twist. 1) .900" long .62-cal (.625") bullet needs 1:65" twist..

Greenhill Formula for Optimal Rifling Twist Rate - vcalc.com

WebCalculates the Miller stability factor. This formula was derived by Don Miller and published in Precision Shooting. This formula is much better than the antiquated Greenhill's … WebThe eponymous Greenhill Formula, still used today, is: where: C = 150 (use 180 for muzzle velocities higher than 2,800 f/s) D = bullet's diameter in inches L = bullet's length in inches SG = bullet's specific gravity (10.9 for lead-core bullets, which cancels out the second half of … desktop wallpaper aesthetic inspirational

What is Rifling Twist Rate? NRA Family

WebThe Miller twist rule is better than the Greenhill rifling formula when measuring the specific gravity (SG) of a boat tail bullet because the Greenhill formula was originally … WebFeb 12, 2015 · The Greenhill formula was created in the late 1800's to calculate (estimate) rifling twist to stabilize a bullet-length. I have found it to be very vague and not useful. Have any of the current gun manufactures (in the past century) come out with any chart for twist rate vs bullet length... WebDec 3, 2010 · To apply the Greenhill Formula using the original 55 grain bullet yields the following, for one brand of full metal jacket (FMJ) military type bullet measuring .647″ in length. The bullet diameter is .224″, which … desktop wallpaper aesthetic for baddies

Smith & Wesson Forum - Barrel Twist Rates

WebAug 19, 2024 · Greenhill formula. T=150 x D _____ R. T is the twist required (number of inches for one revolution), D is the bullet diameter (in inches) R is the bullet length to … WebRemoving bullet diameter from twist and length gives the equation often found: T = 150 * D^2 / L. The Greenhill equation includes no term for muzzle velocity, and several … chucks choice 2020WebThe Greenhill Rifling Formula is used to calculate the optimal barrel twist rate for stabilizing a bullet's flight given the bullet's diameter ( D ), length ( L ), specific gravity ( SG) and velocity ( V ). The resulting twist rate is the length in which the rifling of the barrel … The Muzzle Energy of a Projectile formula is used to calculate the energy produced … The Max Ballistic Range calculator computes the maximum range … The Ballistic Coefficient calculator computes the Ballistic Coefficient a factor … desktop wallpaper animated

"Greenhill's formula is much more complicated in full form. The rule of thumb that Greenhill devised based upon his formula is actually what is seen in most writing, including Wikipedia. The rule of thumb is: The actual formula is: where " - Greenhill formula for rifling twist

Greenhill formula for rifling twist

Twist rate and bullet selection - Modern Muzzleloader …

WebAug 15, 2024 · Don Miller developed this formula as a more accurate way to find an ideal rifle twist rate. Whereas Greenhill was more of a generic formula, Miller’s uses more characteristics of a rifle bullet to arrive a a … http://smith-wessonforum.com/smith-wesson-m-p-pistols/292369-barrel-twist-rates-print.html

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WebMay 16, 2014 · This is a quote from Ballistic ENGLE research Greenhill Formula for Rifling Twists The Time-honored Greenhill formula was originally used for determining … WebSep 4, 2011 · When it comes to shooting conicals, you are talking different considerations, shallower grooves, and the Greenhill formula dictates the use of even faster Rates of Twist in the rifling as the length of the bullet increases, to stabilize the bullets in air. If you like FAST ROTs, the current US military battle rifle now comes rifled with a 1:7" ROT.

WebGreenhill empirically developed a twist formula through testing bullets fired in different twists: Multiply bullet diameter by 150, then multiply the ratio of bullet diameter divided by … WebMay 16, 2013 · S&W standard 9mm barrel twist rate was 1-18.75 or 1-16, (depending on who you talk to.) Five grove, cut rifling is still the standard I believe for all S&W barrels. ... Most firearm manufactures use the old Greenhill formula to determine twist rate. It’s a mathematical formula taking into account the bore diameter, bullet length and velocity ...

For best performance, the barrel should have a twist rate sufficient to spin stabilize any bullet that it would reasonably be expected to fire, but not significantly more. Large diameter bullets provide more stability, as the larger radius provides more gyroscopic inertia, while long bullets are harder to stabilize, as they tend to be very backheavy and the aerodynamic pressures have a lon… WebSep 30, 2011 · The Greenhill Formula for minimum rifling twist for stabilization indicates that for a .38 bore with a 1 in 26 twist, the max bullet length would be .85" long. While the Greenhill formula would get one close, it is not a positive equation in all instances. Based on that, (Greenhill value of 170 instead of 150), the max bullet length in the 38/ ...

WebMay 15, 2024 · The Greenhill Formula, developed in 1879 by George Greenhill, a professor of mathematics at the Royal Military Academy at Woolwich, London, is the …

WebNov 25, 2024 · The Greenhill formula is obsolete and will give a result with to fast a twist, except in LR, cast bullets (600+ yds). The reason is that the GH formula, doesn't solve for center of gravity. For the last 30 years, I've shot 1.16 - 1.19 long bullets, in my 14 twist Douglas barrel. 1450 fps range. desktop wallpaper aesthetic plantsWebNov 5, 2024 · In 1879, British mathematician Alfred Greenhill developed a simple formula for determining rifling twist rates for stabilizing bullets. Though overtaken somewhat by updated math and software programs, … chuck schoolcraftWebRifling-twist formulas have changed since 1879 because of that, and are particularly helpful when handloading the .223 Remington. Those .223 barrels have twists almost as … chuck schroeder ashland oregonWebJun 26, 2024 · The Greenhill Rifling Formula is used to calculate the optimal barrel twist rate for stabilizing a bullet's flight given the bullet's diameter (D), length (L), specific gravity (SG) and velocity (V). www.vcalc.com Greenhill formula for stabilizing a projectile. Uses velocity, mass,diameter and length. desktop wallpaper adjust windows 10 fitWebOct 3, 2012 · Obviously there are a number of things wrong with his question but I don't think a lot of new shooters understand rifling or how we determine what twist will … chuck scherer facebookWebFeb 24, 2024 · THE GREENHILL FORMULA Twist = 150 x Diameter squared / Length So... I've been reading the ABCs of reloading by Rodney James and now found something … chuck schoolsWebJun 2, 2015 · The Greenhill Rifling Formula is used to calculate the optimal barrel twist rate for stabilizing a bullet's flight given the bullet's diameter(D), length(L), specific gravity … chuck schuchard watertown sd