What do you use to aim your AR-15?
Iron sights? A red dot? Variable optics, an LVPO, a fixed power option?
It doesn’t matter. Okay, well, it does, but it doesn’t matter in regards to this article. Today we are talking about zeroing a weapon sight.
More specifically, the specialized “battlesight” zeroes you can use with AR-15 style rifles. These zeroes are specialized and designed to maximize the efficiency of your AR-15 rifle.
While the concept applies to any rifle or cartridge, these are designed for the AR-15 shooting 5.56/.223 Rem.
But before we dive in, let’s cover some terms and ideas you’ll need to know in order to understand battlesight zeroes.
We’ll also talk about why you might want to consider a battlesight zero and if it’s ultimately right for you.
But first, to get spun up on rifle ballistic terminology, check out the Brownells Daily Defense video below.
Table of Contents
Any Range Zero
Let’s say you want to hit a target at 300-yards, and that’s it.
Do you have access to a 300-yard range? Well, then go out to 300-yards and zero your gun.
Or you can start at 100-yards, then move to 200-yards, and then finally 300-yards to get the zero straight.
This zero method is effective but requires a longer range to zero your rifle effectively. Also, you only know the gun is zeroed to 300-yards.
So what if I told you there was a more efficient and effective way to zero your rifle.
Maximum Point Blank Range
When I was a slack-jawed 18-year old, I remember someone explaining Maximum Point Blank Range (MPBR) and Battlesight Zeroes to me and nodding as if I understood.
I kind of did, but it wasn’t until I got behind a rifle and saw it in action that it clicked.
MPBR is an interesting concept that’s used widely by the United States military but it didn’t come from the military.
Hunters were likely the first to use MPRB with old-school scopes. These days we have fancier models with mil-dot reticles and bullet drop compensators allowing us to compensate for bullet drop.
They allow you to zero at a specific range, often very short, but the zero holds up to hundreds of yards. The military calls them Battlesight Zeroes.
Imagine you have a target that is a 12-inch square. If you can aim at the middle of the square and the bullet’s trajectory doesn’t exceed 6-inches up or down up from 25- to 300-yards your MPBR would be 300-yards.
If the bullet drops more than 6-inches at 300-yards or elevates more than 6-inches at or on its way to 300-yards, you can’t hit your target and therefore do not have a 300-yard MPBR.
Simply put, MPBR is the max range you can aim at a specific sized target and still hit it without making adjustments for holdover.
The Line Game
Before fancy optics, hunters used MPBR.
To better understand MPBR, we need to talk about ballistics and how a round flies through the air.
Set your rifle down and look at the sights compared to the barrel and imagine straight lines coming from each.
As you can see in the picture above, those lines run parallel to one another and do not intersect.
This is known as height over bore. In the picture, the sights are approximately 2.7-inches or so above the actual barrel.
I learned about height over bore the hard way in 29 Palms California, training for my first deployment.
I watched a Marine with an M16A4 topped with an ACOG get in the prone and start firing.
He immediately decimated a rock in front of him and promptly missed his target.
As he aimed at his target with his ACOG, he couldn’t see the softball-sized rock a few feet in front of him and shot it twice without even realizing it.
He obliterated the rock because the ACOG sat 2.7 inches above his bore…and he just couldn’t see it.
This is important to know because bullets don’t fly perfectly straight from the end of your barrel.
When you add sights or an optic to your AR-15, they are positioned to be aimed slightly downwards.
This causes your barrel to be somewhat inclined.
Are You Inclined?
An inclined barrel ensures the trajectory of your round’s point of impact meets your point of aim.
Go back to your straight lines.
Incline the line from your barrel, and it will cross the line from your sights. This is where the point of aim meets the point of impact.
When we zero, we connect the point of aim with the point of impact.
Additionally, that incline maximizes the range of your weapon.
Despite what you might have heard, the bullet doesn’t magically drift upwards when it leaves the barrel. You are aiming slightly upwards.
Like any object on Earth, bullets are subject to the effects of gravity, meaning the second a round leaves the barrel, gravity begins pulling it towards the ground.
The sighting system on AR-15s allows us to maximize our range by aiming slightly upwards. So, bullets go up and then come down in an arc.
As a round travels, it does not stay entirely in line with your point of aim. It can go below, or above it depending on the range of your target.
Here’s the thing…your point of aim and point of impact can meet at two different ranges.
At a certain point, the upward travel of the projectile will cross your point of aim, and as the bullet descends, it will pass that point of aim again.
The first time your POA and POI meet is known as Initial Intersection.
The bullet will continue to climb a bit and, at some point, will reach what’s called the Maximum Ordinate. This is the height of the highest point in the trajectory of a projectile above the horizontal plane passing through its origin.
Once the bullet begins its journey back towards the ground, it will eventually cross your line of sight again, and this is called Terminal Intersection. And that serves as the furtherest zero range you’ll have.
Brownells Daily Defense talks about this in the video below, so check that out.
Two Ranges, One Zero
All that leads to why Battlesight Zeros are represented by two numbers.
For example, the 50/200 zero means that the point of aim coincides with the point of impact at both 50- and 200-yards.
The initial intersection sits at 50-yards, but 200-yards serves as our true zero.
Basically, I can zero at 50-yards, but know I can still land a shot at 200-yards.
Using an MPBR zero, you can also zero at shorter ranges. This proves useful as you may not always have access to a 300-yard rifle range or even a 200-yard rifle range.
Typically, 50-yards, 36-yards, or 25-meters are accessible. So, this makes zeroing a lot easier.
What about the ranges between 50-yards and 200, you ask? What about ranges closer than 50-yards and further than 200-yards? Man, you guys ask all the right questions.
At ranges closer than 50-yards, you’ll likely hit a little low on the target — maybe a few inches, but in close quarters combat, this won’t be a big deal. You’ll still be punching his clock.
And at 300-yards, you’ll be hitting low as well.
Now we can circle back around to Maximum Point Blank Range zero I addressed at the beginning of this whole mess.
That 50/200 zero is an MPBR zero. MPBR typically takes target size into account when planning.
The 50/200 is a defensive MPBR designed for a torso of a human being. That’s a pretty big target.
With the 50/200 zero, I should be able to place my front sight, red dot, or reticle in the middle of a target and hit it at ranges between 50 -and 200-yards with excellent precision.
I will not have to make adjustments to compensate. I bisect my target in the middle and shoot.
Best AR-15 Battlesight Zeroes
Sure it’s not the most precise means to hit a target, but in combat, you want quick and accurate.
An MPBR zero allows you to do nothing more than put a sight on the chest of your target and pull the trigger with a better-than-likely chance you’ll hit it.
Even with a 50/200 zero, your MPBR isn’t 200-yards. Max range to hit a man in his torso could be as far as 300-yards, but you’ll hit him closer to his belt buckle than his chest.
While we’ve talked extensively about 50/200…that’s not the only MPBR on the table.
So let’s examine the different MPBRs and their place within AR-15 shooting.
Keep in mind these zeros are designed for man-sized upper torso targets.
If you want to hunt with an MPBR, rethink these numbers based on the target size and the caliber you’re using.
1. The 50/200 Yard Zero
The 50/200 yards zero is, in my opinion, the best zero for police and civilian shooters.
It’s very precise but does limit you to 200-yards. That said, that’s perfectly fine for most police and civilian engagements.
Most police are unlikely to find themselves in engagements beyond 200-yards.
If a target is beyond 200-yards in the police world, you probably won’t take the shot unless forced to.
Beyond 200-yards makes it a lot easier to miss, and if you miss, where is that bullet going?
Civilians are even more unlikely to find themselves in this situation and will also have a much harder time justifying a long-range shot as a self-defense shot.
The 50/200 zero is highly precise at 50- to 200-yards. With a 50/200 MPBR zero, there is only a 3- to 4-inch difference in point of aim and point of impact from 50-yards to 250-yards.
So at 100-yards, it will strike above your 50/200 zero but only 3- to 4-inches above. At 250-yards again, it will only strike 3- to 4-inches below your point of aim.
Best of all, you can zero your rifle and optic to this 50/200-yard setting at 10-yards.
Frank Proctor has a great video on that below.
2. USMC 36/300 Yards
Do I favor the 36 to 300-yard zero because I used to be a Marine? Maybe, but I also find it to be highly effective and extremely versatile.
Plus, to be fair, I’m better at using yards than meters because I use Freedom units.
Although the Marines adopted the ACOG, which uses meters as its BDC, we still shoot in yards. It was a point of contention on qual day.
The USMC method sees you zero at 36-yards for the initial intersection and that gets you all the way out to 300-yards.
Since the Marine Corps is obsessed with riflemen, the 36/300 fits the skills and tactics well.
From my experience, a 36/300 zero will keep your 5.56 projectile inside of 5-inches from your point of aim all the way out to 300-yards.
It’s boringly reliable and predictable from M4 and M16 rifles and their civilian equivalents. And this translates well to the torso of a human target.
At 350-yards, you can still hit a man in the belly if you aim at his chest — you’ll just see a 5-inch drop from your point of aim. So you can still effectively engage a target out to 350-yards.
The USMC zero is best for extended-range shooting.
At closer ranges, from 100 to 250ish, you’ll hit high but still within 5-inches of your zero.
3. The Army’s 25/300 Meters Zero
The Army made a move to meters — I guess to make it easier to communicate with our NATO allies and better coordinate equipment and gear.
Whatever reason they have is lame, and NATO should conform to us cause ‘Merica.
Anywho the Army’s zero is comparable to the USMC, offering similar range potential. That said, it brings slightly less range than the USMC’s MPBR zero. So it can be a little less precise.
Between 25- and 300-meters, the zero will give you 6-inches of flight variance compared to the USMC’s less than 5.
But the Army’s method is easy to use if meters are your game.
The Army’s zero also allows you to get out to 350-yards, but you can expect a little more than 6-inches of drop.
What About .300 BLK, 7.62, etc.?
What about my AR in .300 Blackout? Or 7.62×39? What about my Mk 18 with a 10.3-inch barrel?
What if I’m using a 150-grain .223 round made of Vibranium?
Good questions. Well, to figure that out, you’ll need a ballistic calculator.
These are easy to use if you have some basic information:
- Ballistic Coefficient of the projectile (read more about that here)
- Velocity of the projectile
- Target Size
- Sight height over bore
StrelokPro is free and can be downloaded to your phone (Andriod Link). You can plug your data and come up with your own MPRB and zeroing scheme.
If you’re on a real computer, ShootersCulator.com has a great MPBR calculator. They also have some other fun things, I recommend taking a look!
We’ve got other recommendations in our Best Ballistic Calculator App article.
The above models are designed for AR-15s in 5.56 and .223 in standard barrel lengths. Don’t get crazy with caliber and barrel length, and expect the same results.
Making your own MPBR is simple and easy. That said, always make sure to confirm your zero at the close end and at the far end if possible. Trust, but verify.
So which zero is for you? Let us know below. Want an optic to go with your new zero? Take a look at the Best AR-15 Scopes & Optics!