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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sextant accuracy (was : Plumb-line horizon vs. geocentric horizon)
From: Jared Sherman
Date: 2005 Feb 13, 00:55 -0500
From: Jared Sherman
Date: 2005 Feb 13, 00:55 -0500
Frank-I'd suggest that's not relevant here. Two minutes of angle ("MOA") at 100 yards would be "typical" but that's a limit of the rifle not the shooter. 1/2 MOA is not unusual in competitions, that is, five rounds in a 1/2" radius. But that's not so much from the human eye, but from extreme skill at holding the weapon steady, and preparing the rifle and ammunition to extreme tolerances, then either judging the wind very well or shooting on a calm day. You'll find resolution limits of the human eye somewhere out there on the web. They vary somewhat as does vision, i.e. farsighted? 20-20? 20-20 is supposedly normal, but 20-10 and even 20-5 exist. Even without genetics, there's a lot of variation in eyes.