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Bart B. · January 28, 2013, 07:46 AM

Some interesting things mentioned in this thread.

Spin drift of the .30-06 round's about 7 inches at 1000 yards; this has been known since the 1930's. Not enough to ever be noticed unless you can shoot your Garand no worse than 1/4 MOA at that range. Besides if you have it zeroed at 600 yards, the bullet's never gonna be more than about 1/4 MOA sideways from the line of sight. Best thing to do is forget about spin drift. No high power rifle shooter I know of that wins the matches and sets the records ever worried about coriolis or spin drift; maybe 1 out of 1000 would always put their first shot at 1000 yards within 5 inches of point of aim anyway, but I never met him. . . .do you get the drift of this?

Best place for the front sight, windage wise, is what lets you get a zero with the rear sight on mechanical zero. That way, you've got maximum windage either side of the sight's windage range, plus, it's easy to remember where windage zero's at on the sight. Do this by first setting your rear sight to zero; index line centered on the middle hash mark. Then shoot a few rounds at 100 yards. Note where they group relative to your line of sight. Then move the front sight about .008" sideways for each MOA you need to correct for; in the opposite direction you want to move the group center. Note the marks on the receiver are .03125 inch apart; that's 4 MOA. Shoot another group; make changes if necessary. Who really cares if the front sight's 1/16th inch off the center of the gas cylinder, anyway?

January 28, 2013, 07:46 AM	#8
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Some interesting things mentioned in this thread. Spin drift of the .30-06 round's about 7 inches at 1000 yards; this has been known since the 1930's. Not enough to ever be noticed unless you can shoot your Garand no worse than 1/4 MOA at that range. Besides if you have it zeroed at 600 yards, the bullet's never gonna be more than about 1/4 MOA sideways from the line of sight. Best thing to do is forget about spin drift. No high power rifle shooter I know of that wins the matches and sets the records ever worried about coriolis or spin drift; maybe 1 out of 1000 would always put their first shot at 1000 yards within 5 inches of point of aim anyway, but I never met him. . . .do you get the drift of this? Best place for the front sight, windage wise, is what lets you get a zero with the rear sight on mechanical zero. That way, you've got maximum windage either side of the sight's windage range, plus, it's easy to remember where windage zero's at on the sight. Do this by first setting your rear sight to zero; index line centered on the middle hash mark. Then shoot a few rounds at 100 yards. Note where they group relative to your line of sight. Then move the front sight about .008" sideways for each MOA you need to correct for; *in the opposite direction* you want to move the group center. Note the marks on the receiver are .03125 inch apart; that's 4 MOA. Shoot another group; make changes if necessary. Who really cares if the front sight's 1/16th inch off the center of the gas cylinder, anyway? Last edited by Bart B.; January 28, 2013 at 08:13 AM.