I appologize if this has been asked many times and I really have a difficult time with the search function of the forum.
I typically shoot Lake City 55 grain FMJ in my 20" AR. To get the most out of the ammo, what should I sight in for at 100 yards to be close at 200 and 300 yards?
To "get on paper" at 25 or 50 yards with a new scope, what would be the over or under be at 25 yards? I guess what I am asking for is a trajectory chart for the 55 grain.
Check the Information/Guides tab above.
There's info there on sighting in an AR.
In addition to the info mentioned by JoeInCt, the Maryland AR15 Shooters Site includes a Zeroing Methods section along with a variety of charts of Zero Trajectories. Check out the Improved Battle Sight method: "It keeps the bullet within 2" of the point of aim from 8M to 220M."
According to Shoot v3.0 for XM193:
Set sights to shoot 0.71" High @ 100y Target for a 200y Zero.
Set sigths to shoot 2.55" High @ 100y Target for a 300y Zero.
. . . 1.44 Low @ 25y for a 200y Zero.
. . . 0.98 Low @ 25y for a 300y Zero.