Whats your Red Dot Zero? 25-50-100 yrds?

[Pappabear]

I have two sight aiming systems. The ACOG with Doc on top. On that rig I have the crosshairs zero at 100yrds, and the red dot at 25yrds. The Red dot is 8moa, so its pretty much built by design to CQC.

My Aimpoint M4's is zero at 100 yards. When I was practicing drills last weekend, my POI was low at 25 yard shots. I knew this would be the case.

Two questions:
what is your Red Dot Zero, & why?
If you sight in at 100 yards, what is the trajectory supposed to be at 25-50-75 yards. I will shoot it soon enough at the range, but thought you experts could shed lmore light. As always, thanks!

[Parabellum9x19mm]

i'm no expert....i'll give my opinion anyway tho, cos i have nothing better to do

in the Army they have you zero at 25 meters, because the 25m zero is the same as the 300m zero. at 50, 100, 150, etc you will be holding low to put rounds on target. how much you hold depends on the range in question.


i zero my red dots at 100.

up close, if my life is in danger, i'm going to zip the threat up with multiple rounds and an inch here or there wont make a big of a difference if i'm aiming for upper center mass.

[Derek_Connor]

Assuming its a 16inch barrel, with average sight over bore height (for an AR15), and pushing approx 3100fps with a 55grain projectile:

Here are the paths for a 25,50,100 yard zero, choose which one is more applicable to your use and go for it:


Red = 25 Yard Zero_____________________Green = 50 Yard Zero____________________Blue = 100 Yard Zero

[cz7]

Assuming its a 16inch barrel, with average sight over bore height (for an AR15), and pushing approx 3100fps with a 55grain projectile:

Here are the paths for a 25,50,100 yard zero, choose which one is more applicable to your use and go for it:


Red = 25 Yard Zero_____________________Green = 50 Yard Zero____________________Blue = 100 Yard Zero

i use in all my weapons the 50 yard which works best even on scopes -if i know this zero with range reticule it works out very well ...with buis/is the same thing -most social engagements are under 300 yards - for the best marriage of bullet and target is to work out a ballistic pattern of the ammo used like 50 yds zero .

[vicious_cb]

Does anyone know the exact height over bore for various red dot sights and their mounts? Ive been using 2.5" with a T-1 + LT mount.

[critterdoc]

Assuming its a 16inch barrel, with average sight over bore height (for an AR15), and pushing approx 3100fps with a 55grain projectile:

Here are the paths for a 25,50,100 yard zero, choose which one is more applicable to your use and go for it:

Red = 25 Yard Zero_____________________Green = 50 Yard Zero____________________Blue = 100 Yard Zero

Greetings from south Looziana.

Here be a complete newbie to ARs who is struggling to understand the 'backside' of several of the charts in this five star go-to-school-thread. To date I've attended one single full day carbine course at Elite Arms Training in Lumberton, Mississippi with a loaner Bushmaster which I fired for look-n-feel at a local range for approximately two hours several days before traveling to school, spent many hours reading several excellent forums, and have recently taken possession of my first personal AR, a Daniel Defense M4. Without doubt the BRD bug has bitten me hard.

Until today I was clearly of the impression that an outbound 25 m zero would reacquire the zero mark approximately 300 meters out, pending round specs and external variables. I'm confused because I do not see anything approximating that relationship in the most of the ballistic charts in this thread. What am I missing? Send help.

Thanks,

Michael, a/k/a Doc

[Jim D]

Greetings from south Looziana.

Here be a complete newbie to ARs who is struggling to understand the 'backside' of several of the charts in this five star go-to-school-thread. To date I've attended one single full day carbine course at Elite Arms Training in Lumberton, Mississippi with a loaner Bushmaster which I fired for look-n-feel at a local range for approximately two hours several days before traveling to school, spent many hours reading several excellent forums, and have recently taken possession of my first personal AR, a Daniel Defense M4. Without doubt the BRD bug has bitten me hard.

Until today I was clearly of the impression that an outbound 25 m zero would reacquire the zero mark approximately 300 meters out, pending round specs and external variables. I'm confused because I do not see anything approximating that relationship in the most of the ballistic charts in this thread. What am I missing? Send help.

Thanks,

Michael, a/k/a Doc

Here is a chart showing the 33yard zero...the 25 would cross even further out.
https://www.m4carbine.net/showthread...325#post415325

Here is the 25 yard zero shown:
https://www.m4carbine.net/showthread...738#post435738

both in this thread.

[DocGKR]

Both 50 and 100 zeros work; a straight 25 yd zero has no place in the real world... Personally, we generally use a 100 zero on RDS equipped rifles.

[TexasAg]

Greetings from south Looziana.
Until today I was clearly of the impression that an outbound 25 m zero would reacquire the zero mark approximately 300 meters out, pending round specs and external variables. I'm confused because I do not see anything approximating that relationship in the most of the ballistic charts in this thread. What am I missing? Send help.

Thanks,

Michael, a/k/a Doc

The confusion is being caused by ammo selection and the fact that these charts are in yards, not meters. These graphs appear to be for M193. A 25m zero with M855 generally results (depending on a number of factors) in a zero at approx 300m.

[critterdoc]

The confusion is being caused by ammo selection and the fact that these charts are in yards, not meters. These graphs appear to be for M193. A 25m zero with M855 generally results (depending on a number of factors) in a zero at approx 300m.

Ammo and meters:yards (1.00:1.09) variance were the only things I could think of when I pondered those charts but some of those 30 yard plots looked far more extreme than I would have expected. Can I assume that ammo selection is the predominant factor that will skew the presumed 25/300 meter (?yard?) return to zero point, and that I just learned that knowing one's ammo is critical in anticipating predictable shot behavior at significant distances from zero?