It talks about a combat zero for your AR15 and gives resons why the 100 zero is the best for "combat". I dont think Ill ever be in combat but the guy makes great points that make sense.

Still seems as good today as then, if anything more could be added to it from the experiences of others. I was told all the same stuff, but I still like a high bullet rather then a low one. I shoot low. but that is a personal preference gained from alot of shooting.

Choose your zeroing scheme based on the pertinent facts; not nonsense about “shooting through a cone.”  When shooting at human targets, in the grand scheme of things there isn’t going to be any practical difference between a point of impact on the target that has a negative deviation from the point of aim, (e.g. the bullet strikes 1.5” below the point of aim) and a point of impact on the target that has an equal positive deviation from the point of aim (e.g. the bullet strikes 1.5” above the point of aim.)  In other words, the absolute value of the point of impact from the point of aim (how far the point of impact deviates from the point of aim, regardless of whether it is a positive or negative deviation) is what we need to be concerned about.  Therefore, one of the main points to consider when choosing a battle-sight-zero is this:  What zeroing scheme produces the smallest absolute values for the deviations of the points of impact from the point of aim, over the distance that we reasonably expect to engage a human target in our intended usage?

The chart below illustrates the above concept.  The chart compares the absolute values of the deviations of the points of impact from the point of aim (0.0 inches on the graph being the point of aim/line of sight) for a 50-yard-zero and a 100-yard-zero, using Hornady 5.56 TAP T2 ammunition.





As you can see in the graph above, from the muzzle (0 yards) to approximately 62 yards, the 50-yard-zero has a slight advantage over the 100-yard-zero.  Between the distances of 62 yards and 165 yards, the 100-yard-zero has the advantage.  From the distance of 165 yards out to the 250 yards shown in the graph, the 50-yard-zero has a distinct advantage over the 100-yard-zero.  Choose your zeroing scheme based on the pertinent facts.


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If you join the military you will understand why and how he has formed this opinions.  

keep in mind you don't know who he is, the extent of his training, knowledge, equipment, what unit he was in and what type of "combat" he was in.

use logical reasoning and facts to choose a Zero for your weapon.

With the amount of replies I feel like that FAQ is a lil outdated.

Kyle Defoor once wrote a great article about different zeroes but unfortunately, it's not online anymore. He prefers a 100 yard zero, as do Larry Vickers and Paul Howe.
On the flip side, if you've read Kyle Lamb's excellent book 'Green Eyes, Black Rifles', you'll know that he prefers the 50 yard zero, as do Mike Pannone and Frank Proctor.
One thing Kyle Lamb mentioned is that you should select your zero based on flexibility and not to fit a given situation.

nm...