The More You Know: What Is The Best "Zero" On An AR15? 

Thanks for the description of the various zeros, what optics they are suited for, and for pointing us to the Vortex chart. That is really handy!

So how about an in depth discussion on the subject of sight height above the bore and the effect it has on trajectory perception.

Good info straight to the meat & potatoes

What it means is, zero to ur "cold bore."

With a 36yd zero and 55gr, 16"bbl and 1:7 mounted Eotech XPS 3-0 we see printing of about 6-8" high at 100. Everything I see says we should be 2.5-3" high at 100. What are we doing wrong?

Love to know what percentage of AR owners have shot 300 yd fargets ? We hear the term “ Battle Zero “ Civilians are not preparing for battle. The vastmajority are preparing for home defense. I use a 100 yd zero as all adjustments hold abpve desired impact. 25 yds is 2.5 “ low due to height over bore . 200 yds is 2.5” low. A mid to high chest hold will impact center mass 0 to 200 yds. No bullet is above the 100 yd zero point. Citizens living in open terrain may prefer 25 or 36 yd zero. But if you engage a target at 300 yds and claim self defense, you are on shaky ground. Everyone lives a different scenario. But in a crisis, almost no civilian remembers trajectory tables. Being able to hold in one position to 200 yds simplifies the equation. This is my solution. Everyone needs to find their’s.

A good zero for anyone when application for the optic mounted on an M4 is variable is a 25/300 meter zero, or, for an optic mounted on an A2/A4, a 36/300 yard zero. These zeros will yield good hits on the E type target from center mass hold from muzzle to 350 meters and even out to 400 meters when aim is at head area. Now, since a zero is always just a value for where the sight is resting it is always best to know sight adjustment needed from the resting place to any distance a target may appear. This is easy to do using a ballistics app and chronograph which will identify the trajectory of your bullet from any initial zero. Also, learn MOA and mil value at target distance to understand sight adjustment need, as well as range to distance from MOA or mil scaled reticle as these are skills tied to optic performance shooting at a target which initially presents itself at an unknown distance. Finally, if you do not have the desire or capability to adjust a scope from zeroed distance to actual distance target appears then stick to a hundred yard zero and bench shooting. It’s fun for awhile and some basic marksmanship skills might be developed there. Your imagination can serve all other perceived needs since their reality will never manifest themselves.

Delta34 did a huge brake down in 2 videos that are easy to follow about zeros, I suggest you check it out.

the chart says .224 caliber. just wanted to mention..... good videos