AR-15 zero opinions

[Killabee-23]

Hey guys so i just got a new vortex 2-7x32mm scope for my AR and i havent zeroed it yet. Im trying to debate on what zero yardage i should do i was thinking 50 because i know alot of people who say thats the way to go but i know some other people who say i should zero at 100 yards. the scope booklet says i should zero at 100 but the thing is im probably not going to be punching out further than mabey 400 yards i want to be able to use my scope for semi good CQB and decent long distance. Not just long distance i am really debating on weather or not to zero it at 50 or 100 yards. Whats do you guys think what would you zero it at? Keep in mind my AR has a 1/9 barrel twist and im using junk 55 gr pills and i live in Vermont so theres not many spots where i can shoot over 300-400 yards im not going to be using it for hunting or anything just self defense, plinking and general training. So what do you guys think?

[Art Eatman]

I've always sighted in my centerfires for two inches high at 100 yards. That's generally dead-on at 200 and six inches low (+/-) at 300. I learn the trajectory of any given load and do the appropriate holdover for anything beyond 300 yards.

For a specific range for paper targets, I'll sight in for that distance. But, I'm mostly a hunter...

[ocharry]

i put mine on at 50,,,and i havent tried it at 300 but my streloc app says its a hold on at 300 and still be in the kill zone,,,,i have had it to 150 and it is all good,,,,so i have no reason to doubt that it will be there if i need it

i have killed coyotes at over 100 same set up,,,just works for me

you should try it at both yardages and see what you like or what works for you

my .02

ocharry

[Fal 4 Me]

It depends on the reticle of the scope . If it has a BDC reticle I would zero it in for 100 yards and learn to use the drop marks. If it's a standard duplex reticle I would zero for 50, because that will keep the trajectory of the bullet within 2.5 inches above or below the line of sight out to about 250 yards.

[ms6852]

I like doing 25 meters, it gets you on paper a lot faster, and this is good to 250 yds. Than I re-zero at 200 yds. For me this gives me the best accuracy as I already know how the bullet will perform on my rifle at that distance

[FrankenMauser]

Most of my centerfire rifles, AR or not, get sighted in for 100 yards or more.
Some of them have some kind of "MPBR" calculation factored in, like my .270 Win sighted 2.72" high at 100 yards for a 6" and 280 yard MPBR; but some do not, like my .223 varmint AR upper that's dead-on at 100 - but the trajectory created by the 2.6" sight height somewhat compensates at longer range.

The only major exceptions in my house are a few rifles that aren't really intended for much more than 75-125 yards. The .458 SOCOM, .475 Tremor, and .444 Marlin (Marlin - not the Handi-Rifle) fall into that category. They're sighted in for either 50 or 75 yards - sometimes both (irons and red dot co-witnessed).


So, if it were me, I'd go for 100 yards. Up close, you know you'll hit no more than 2.6" low (standard AR sight and scope height) - and even by 40 yards you're no more than 1" low. And with most 55 grain bullets at 2800 fps or more, you're good to about 200 yards without worrying about hitting more than 3.5" low.

[TnTnTn]

The scope on an AR is a good bit above the bore line so this gives an apparent flattening of trajectory as the range increases. I zero my .223 ARs about 2" or so high at 100 yes and the trajectory is flat enough to hold on coyotes out to 225 yds or so.

[Erno86]

I usually zero mine at whatever the yardage to the backstop berm is...be it 100 or 200 yards at our range --- So I can easily nail any pinecones, clumps of dirt, golf or tennis balls on the dirt stone berm, and any steel targets that have to be placed near the backstop berm.

[Killabee-23]

it is a BDC dead hold redical but if i zero it in at 100 yards what would the hold be at 25 to 50 yards?

[rickyrick]

If you zero at 100, then 25 and 50 hits would be low somewhere between the distance of your scope over bore height.
If you scope is zeroed for 100, go back and shoot 25 and 50yds to see what it does then you would know for sure

[FrankenMauser]

For the Crossfire II 'Dead-hold' BDC reticle, the subtensions for the bars on the lower post are 1.5, 4.5, and 7.5 MoA. The bottom of the post is 11 MoA.

With the 2,800 fps / .235 BC / 55 gr / 100 yd / 2.6" sight height example I used above, this is what I get:

About half way between center and first bar: 50 yards.
First bar (1.5): 25 yards / 165 yards.
Second bar (4.5): 215 yards.
Third bar (7.5): 243 yards.
Bottom (11): 275 yards


With better information on the barrel and ammunition, those numbers could change a bit.
What are the specs on the barrel, and what type of ammunition are you using?
Have you verified any muzzle velocities?

[Llama Bob]

Unless I've got some specific optic or shooting application I'm dealing with, I generally go for a 200y zero which is typically also a good CQB/25y zero for military type rifles.

For rifles with optics capable of dialing drop it results in different drops, but that's not really a big deal and the added short range capability is nice.

[agtman]

The various AR zeros were covered in detail in Travis Haley's "Make Ready" video (Panteo Production).

For practice purposes and general range plinking, a lot of AR owners default to the 100yd Z.

For "combat" or defensive use, the two most popular (because they are the flattest shooting) are the 50/200 meter Z and the 36/300yd Z. The 36/300 is actually the flattest (i.e., least rise, least drop out to 300yds).

There will be variations in these zeros depending on whether you're doing it in yards or meters, and depending on the barrel length of your AR (16", 18", 20") and the ammo you are zeroing with (55gn v. 62gn v. 75-77gn).

Whichever variables happen to be in play with your particular AR, it is critical that you verify POI at both the shorter AND the longer zero distances with whatever ammo you're shooting, and then if you find you're "off," make sight adjustments as needed and then continue to verify your Z until you're "on" at both distances.

[marine6680]

I tapped wrong...

100yds is the way to go on a scope, many AR scopes have hash marks to help with hold overs. I wouldn't trust a drop calculator reticle to be accurate, but mil or MOA hash marks are easy to use for hold over.

50yds is great for BUIS and red dots. Out to about 250yds. It is the flattest trajectory between 0 and 225ish yards. (Using 55gr 5.56)

[noonesshowmonkey]

I am partial to the 36 yard / 300 yard zero that the USMC uses.

That said, for an optic, I would consider using ranges specified by the manufacturer or defined by a mission profile. The ACOG, for example, has a set zero of 100m because it's hash marks correspond to various points along the trajectory of common .mil 5.56x45mm loads.

[RiponP90]

I've always zeroed at 100 yards. I find that it goes much quicker for me. In the Army we usually did 25 yards but when we got to do 100 it was a blessing. Much quicker and in my opinion I trust it more even though a zero is a zero if it is done properly.

[9x45]

For 3 gun competition I use a 35/300 yard zero that yields a 8" window from 0 to 330 yards. The scopes are Trijicon 1-4 Accupoints.

[wpsdlrg]

I voted for 100 yards, as there were only two choices offered. However, I actually prefer to zero at whatever the longest "normal" distance at which I will shoot a particular rifle. For myself (and the M4 flat top clone I have), that is 200 yards. 90 % of my shooting of my AR will be at that distance or less.

I do this, as a matter of course, with all of my rifles. I find it easier to hold a bit low at intermediate distances, than to hold high (which would be required if I zeroed at a shorter distance).

I will occasionally shoot the AR at distances beyond 200 yards, such as 300 yards, but that will constitute 10 % or less of my shooting with that rifle.

For my other rifles, the zero distance varies, but is based on the same "rule" as stated above.

Just my preference, not claiming any advantage to this. To each his own.

[Killabee-23]

yeah at my local range it is only 100 yards to the berm so i just sighted it in to 100. It was freezing cold out so i wanted to leave asap so as soon as i got it where i wanted it i left. Lol i still have some fine tuning to do it might be 1 to 1 1/2 MOA right but i saved my clicks so when i go back i can just start from there hopefully it wont be freezing balls outside lol thanks for all your opinions and help guys keep on fighting for our second amendment rights. And dont be one of those guys who walks into an applebees with an AR-15 strapped to there chest rig looking like he belongs in a desert in Afghanistan. It just makes all us gun owners look bad unless theres a second amendment rally going on or something of that nature dont do it.


A free people ought not only be armed and disciplined.
But should have sufficient arms and ammunition to maintain
a status of independence from any who might attempt to
abuse them. Which would include their own government.

-George Washington-

[raimius]

Personally, I go with the 50m zero for 55gn loads. It provides a reasonably small window of elevation change out to 250m. That said, if your scope has BDC marks for the load you use, zero it to the recommended distance, or your BDC marks will be off.

[Skadoosh]

Scope: 100
Reddot & irons: 50