The information on the 700 Remington is from a book called "The Remington 700, 25 Years" by John Lacy.
Here are the ones in the book:
.222 Rem, .222 Rem Mag, .22-250, and 458 Win Mag - 1 in 14" twist.
.250 Savage, .257 Roberts, .25-06, .270, .308, .30-06, .300 H&H, 8mm Rem Mag, and .338 Win Mag - 1 in 10" twist.
.223 Rem, .375 H&H - 1 in 12" twist.
.243, 6mm Rem - 1 in 9 1/8" twist.
7mm-08, 7mm Mauser, 280 Rem, 7mm Rem Mag - 1 in 9 1/4" twist.
.308 Win, Varming Special - 1 in 12" twist.
.350 Rem Mag - 1 in 16" twist.
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I am not sure why you want to update Greenhill, except maybe for something like the .17 caliber, which IIRC Greenhill doesn't cover. To do so would require a lot of both computer work and actual experimentation. The Greenhill formula will produce an ideal twist rate. But firearms engineers don't work in an ideal world. They have to produce a rifle in, say, .30-'06, that will be reasonably accurate with bullets from 110 grain to 220 grain, plus the Remington Accelerator. They know all about the Greenhill formula and have some of the best ballistic software in the world, but still have to compromise. The alternative would be to tell the buyer of a Remington 700 in .30-'06 that he can use only one specific bullet if he wants accuracy, an approach not likely to make many friends for the gun company.
For forensic purposes, police firearms examiners (misnamed "ballistics experts") have access to data provided by the factories. For obsolete guns, especially handguns, they have Matthews and other reference books. I am much afraid you would be re-inventing the wheel in that area, but have fun.
Jim