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View Full Version : AR-15 Sight Height - Zero and POI


ExtremeX
05-27-2012, 12:33 AM
I'm just spending a little time playing around with my drop calculator and wanted to check the numbers on a couple things.

I know sight height varies due to different mounts and optics, but wanted to replicate the typical Improved Battlesight Zero often recommended for RDS users.

With a 50 yard zero, the bullet often times returns at 200 yards. This was confirmed when I used a 2" sight height.

When I change the sight height to around 3", which I think is what is usually found on scoped rifles using things like a LaRue SPR mount, the 200 yard POI is actually around 2.9" high.

Seems like you are actually better off with a 100 yard zero at this point. (shows -1.0 at 50; and -1.2 at 100)

Does anyone know the actual sight height of an Eotech and/or Aimpoint Micro?

Does anyone know the actual sight height of a scope with a 30mm tube in a Larue SPR mount?

Seems like the general recommendation zeroing a rifle at 50 yards can greatly vary depending on ones individual setup.

G60
05-27-2012, 12:45 AM
Irons are 2.5", a lower 1/3 co witness RDS is 2.8" (might actually be something like 2.83" to be exact, I forget.)

tonyxcom
05-27-2012, 7:37 AM
Larue SPR mounts like the LT104 and LT139 have height over bore of 2.7".

SuperSet
05-27-2012, 1:55 PM
I agree with above posters on their sight height and actually prefer the high ADM/LaRue scope mounts at 3.15".

ExtremeX
05-27-2012, 2:07 PM
I just did some searching and found the Eotech sight height to be around 7.2cm, which is 2.8"... Not sure if this is with out without the 7mm riser built into the QD versions.

If anyone was wonder I was running the ballistic drop calc with generic data, so its not 100% accurate, but it was only to give me an idea of what to expect.

I think I will end up picking my own custom zero based on the actual sight height and drop chart for my rifle. The goal is to achieve the best zero to give the projectile the flattest flight path across the 0-200 range instead of just going with the generic 50 yard zero.

I will probably continue zeroing my scoped rifles at 100 yards based on the data I see. I typically dial in correction for drop here so its not really an issue one way or another.