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Spin drift of the .30-06 rounds about 7 inches at 1000 yards; this has been known since the 1930's
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Long before that, Gen Hatcher (then Major) wrote about it in his book, "Machine Guns, 1917".
In the book he has a chart showing the drift of the 1903's 1905 sights and 1906 Ammunition, to 2800 yards.
Briefly he shows the drift with this combination to be 1 ft at 1000 yards, 2 feet at 1200, 4 at 1400, 6 at 1600, 9 at 1800......and 36 feet at 2800 yards.
I realize few of us shoot past a mile, and those that do successfully know the formula's to compensate.
Some sights for military rifles had the correction built in but WWII shortened the ranges between combatants quite a bit, no longer were soldier dropping rounds into their adversary's trenches at 2000 yards.
I put a dial indicator on my '98 Krag and its 1901 ladder sight, it seems to move a tad to the right as you push the slider up. (I just roughly checked, I'll mount the rifle solid and try it again.)
When we went to the M1903A3, and its peep (rear) sights, they were limited to about 800 yards in elevation (the Garand & M14 goes a bit further).
But for the average soldier its not something to be concerned with (excluding snipers and SDMs).
It's still taught to machine gunners or was, I taught "spin drift" when I use to run MG schools with the M60. Now it seams most people use machine guns as an automatic rifle instead of a crew serve weapon to support troop in the advance.............any way.
For the new shooter trying to determine which way to move the sights to change the impact, Spin Drift, the Coriolis Effect, etc etc, should be put on hold, there are too many other things to worry about. Wind and Mirage are more critical.
With the M16 and qualification going to 300 yards, its much to do about nothing. If you're shooting 1000 yard service rifle matches at 800, 900 & 1000 yard you're going to have (or should have) a specific zero for those ranges which would take into account spin drift.
The Coriolis effect is something different, besides distance, the lay out of the range makes a difference. It will be different if your range lies east and west or north and south, and the latitude and longitude of that range, (that's why we have "score or data books").
So in short, for the new shooter, DON'T WORRY ABOUT IT, Learn the fundamentals and learn to read wind and mirage. You'll be much further a head.