There is a certain satisfaction that comes from being able to hit a bullseye without the use of a high-tech scope or red dot sights emitting optic.
With iron sights, this how-to guide will teach you how to get that bullseye and become an expert at aiming without high-tech optics.
- How to Zero Iron Sights and Have Deadly Aim
- What Is Zero?
- Last Reminders
How to Zero Iron Sights and Have Deadly Aim
We have created 5 steps to guide you on how to zero your iron sight. We came up with the acronym ILDAF to help you remember the steps below:
Step 1: Identify Your Target
Most people choose 25 yards as their target. It lessens the difficulty because it brings each square’s width and length at 1 MOA.
What Is Minute of Angle (MOA)?
Adjusting the back up iron sights isn’t as simple as trial and error. It’s helpful to know the basics and what a Minute of Angle (MOA) is to ensure your sight adjustment and clicks would lead to zeroing in the iron sights.
The “unit of measurement” for iron sights is commonly referred to as Minute of Angle or MOA. It’s imperative to know that sights operate in angular measurement. At short range, the bullet impact of an angle change in MOA might be minuscule.
The importance of zeroing your back up iron sights would come more in handy as you increase distance.
Visualize this: 2 people using a compass to guide them as they walk 100 yards forward. A compass contains 360 hash marks – each mark incredibly close to the next.
Person A starts to walk at the 90-degree mark, then Person B walks at 89. At the starting point, both are right next to each of them.
But they would end up a meter and a half away from each other at the end of 100 yards.
If compasses operate in degrees, iron sights come in angles. Every angle affects accuracy. Every degree contains 60 segments. Each segment or one-sixtieth of a degree is 1 MOA.
To realize the change in every MOA, 1 MOA adjustment results in an inch of diversion in every 100 yards.
Clicks highly impact accuracy thus you have to know the change in MOA of your rifle per click adjustments. For reference, most adjust at 1/4 MOA per click.
With this, the iron sight adjustments are easier to calculate as well. The target or the middle diamond measures 4 MOA wide, the accepted accuracy for the U.S. Army. If it’s US Army approved, then it’s all good.
Meanwhile, the back of the target would be 16 MOA. It’s fairly easy to get it right at this distance. Working with a similar accuracy standard, one can move the target further back to 100 meters. You can check if you have sight zero if the results are fairly close.
You can use papers with readily printed targets for practice. Otherwise, you can mock up one by using an old paper plate with a target marking in the middle. You just need to check the measurements to help you with your accuracy.
Step 2: Load Your Rifle
This is pretty self-explanatory but an important step. Achieving iron sight zero is affected by the rifle, range, shooter, and ammunition.
Many times, some have a “practice ammunition” which is different from what they really use outside training. Although it helps the shooter practice the rifle, it is not a recommended practice if your goal is to confirm and lock in your sights.
The thing is, each ammunition cartridge calls for a different zero. Thus, if you want to know the actual sight zero of your firearm, practice with the ammunition you would be using.
Pro-shooter tip: If for some reason, you prefer to have a practice load and “real” load, you can record and measure the difference in sight adjustment using colored markers.
This can help you determine and estimate the bullet impact of each load. It can help you adjust to the difference when you switch to another load.
Step 3: Determine Your Shooting Position
More important than identifying your practice range would be your position.
A shooting bench might seem tempting as it can easily help you sight in and gain stability when shooting.
Take note though: This won’t be your real position when shooting outside the training course.
If you aim to zero the sights, we recommend practicing in a prone position.
When it comes to shooting, it might be better to start with this position. It would be easier to adjust to a bench than to adjust from a bench to a prone position.
If one gets too used to shooting from a bench, it might be hard to adjust when shooting in an actual field. Remember, you’ll only get your zero outside your comfort zone. Practice it from where you actually plan to use it.
So, should you go with a cross ankle sit position? Aside from the prone position, others fire from a cross ankle sit.
You can try both and see which one works better for your chosen range. After determining your position, take note of your natural point of aim. This helps you achieve and enhance your level of accuracy in your back up iron sights.
Step 4: Adjust Rear Sight
This is only applicable if your rear sight is adjustable. If not, proceed to the last step.
Most sights have a “zero” setting. This is common especially for those with adjustable carry handle rear sight. Some even come with a guide to get the right number settings.
For back up iron sights with BDC, it is helpful to set these on a specific setting before beginning to align the sights.
This is true for KAC Micro, Magpul MBUS Pro LR, the carry handle sight, or a Matech.
These usually come with instructions, so adjust the rear sight elevation to baseline before proceeding to the last step.
Adjusting the rear sight requires that the aperture is strictly centered in the housing. You can achieve this by moving the aperture all the way to one side.
Record how many clicks it would take to reach the other side. Divide this number by half. This would indicate the number of clicks you need to put in the center.
Step 5: Fire and Adjust
Others go for three or five shots before they do any front or rear sight adjustments.
While three is easier to remember the aiming position for each round, five gives you a more accurate group of data points. Depending on your level and objective, choose which one works better for you.
If you’re a beginner. expect to have a spread of points in the first few tries. You need a tight group of shots before you can effectively adjust as needed. Otherwise, you might end up like a dog chasing its tail and achieve nothing.
When you have a good set of shots, note if elevation adjustment or adjusting windage is necessary.
You can opt to fix both at the same time or adjust them one by one.
How this might look like:
- Adjust the windage first
- Fire a shot or two
- Check for elevation
- Check the bullet impact of a group of shots and repeat as needed
It might take a few batches but patience is key here. If the problem still persists, you can try adjusting the front sight post of your gun.
A bullet tip or small tool can make adjusting the front sights easier. Look for the arrow which points to the way it should spin. Moving it in the same direction would raise the POI and front sight post.
Fire a last group of shots to confirm your iron sight zero. Again, your zero is only good for your chosen distance.
If you zeroed at 25 yards, it doesn’t mean it would also work the same way for 200 yards. If you want to lock in for 200 yards, move your target accordingly then fire at this distance.
Those are the basic things you need to remember when zeroing iron sights. Remember ILDAF and you’ll be ready in no time. We have a couple of tips below to further get it right.
What Is Zero?
A lot of people might be intimidated by using back up iron sights, let alone zeroing them.
However, this shouldn’t be the case. Consider it as knowing your rifle more and how you can bring out and master its potential using whether you use stock or back up iron sights.
Zeroing your front sight and rear sight simply refers to proper sight alignment when you fire a shot.
Each level and turn in the sights give off a different angle and point of impact. Thus, you want to achieve a zero wherein both irons are aligned enough to hit the bullseye.
Whether you have an AR 15 or an M4, all guns with sights need to be zeroed in.
How Often Do You Need to Zero Front and Rear Sights?
A lot of shooters don’t realize how often this process should be done. If you are unsure if you need to zero your rifle, chances are you need to do it.
Sighting your AR 15 rifle or any weapon should actually be considered part of the maintenance process. Before proceeding to mounting a scope or set of optics, zeroing should be done first.
These are the key indicators that signal a need for zeroing process:
Any change in these 6 factors would require the shooter to recalibrate and adjust again.
For example: If shooter A has achieved the zero for a certain AR 15 rifle, then shooter B uses the same AR 15 rifle, shooter B should begin another zeroing process.
Two AR 15 rifles under the same series would also need two separate alignment processes. A different scope or optics would definitely require the shooter to start over and re-zero.
Change in conditions should prompt another procedure too. A higher or lower elevation, as well as wind strength and direction, are crucial factors too.
The same is true when the user changes the weapon or ammunition load.
Each weapon and rifle cartridge has its own zero. The load of the AR 15 rifle has a lot to do with the sight zero – it affects the zero and becomes highly noticeable in long-range shooting.
Why the Need to Zero?
To assist you in zeroing your back up iron sights, it’s important to understand how these work.
Iron sights basically have the same look but are constructed differently. If you have similar sets but one has peep sights and the other has a blade, the rule applies the same way.
This means that every sight adjustment made might have a different impact on another set of iron sights.
The trajectory angle or ballistic arc is a concept that should be clear to any shooter.
It is a common misconception that bullets naturally rise when fired – they don’t. Due to gravity, they travel in a loop direction. In contrast to our line of sight wherein we see things in a linear direction, bullets go downward as they travel.
If you look closely, the front and rear sights do not have the same height. The rear sight is actually longer than the front sight.
The reason behind this is it will cause the shooter to angle the rifle upward when zeroing in. This accounts for the trajectory angle and helps the bullet in the initial launch.
The barrel is angled slightly upward. The bullet trajectory would end at the target, as it meets the shooter’s line of sight.
A confirmed iron sight zero is when the ballistic arc of the bullet and your own sight intersect with one another.
In the next section, take note of the following terms: Point of Aim (POA) and Point of Impact (POI).
Point of Aim (POA) simply refers to where you are keeping your sights on when your sights are aligned while Point of Impact (POI) would refer to where the bullet lands.
Rear Sight and Front Sight Adjustments
It is also important to know your rear sight and front sight, as well as understand the result of adjusting each or both.
Vertical Adjustment is required when your point of impact is higher or lower than your desired target. Vertical adjustment to the front sight is also referred to as elevation.
To adjust elevation, move your front sight higher and adjust the rear slightly lower. If your POI is lower than POA, adjust your front sight lower and your rear sight a bit higher.
Horizontal Adjustments, also known as windage adjustments, are necessary when there are sideway inaccuracies.
Windage adjustment is necessary when your final point of impact lands to the left or to the right. If your front sight controls windage, adjust it to the left.
If it’s the rear sight, again, move it to the same point you want your POI to shift to. Always take note of your MOA adjustments so you can refer back to them when needed.
You can learn more about this in our guide on How to Adjust Iron Sights Accurately.
- Before you rush to buy the next investment for your rifle, consider learning and using standard or back up iron sights first. Not only are they more durable and cheaper, but they can also offer accurate targeting once you’ve mastered using them. Mastering this primary sight is a must!
- Take into account the type of rifle and your target spread. This should affect how you pick the distance you want to aim for. For those who are starting and are unsure, a safe range would be 25 yards or 50 yards.
- When one gets used to an arbitrary distance, this is often used as their point-blank or also known as “battle sight zero”. The actual impact on the target becomes automatic when the shooter aims from this range. This is how the “set and forget” behavior develops.
- Take note of external conditions. You need to account for wind as this affects the ballistic angle. For example, if you confirm your zero at 25 yards with windy conditions, you would have to set your gun or rifle again when there is more or no wind on a different day. Over time, one gets to estimate and compensate for the aiming point and shooting position in different wind conditions.
And there you have it! That ends our tutorial on how to zero iron sights. With the plethora of optics and specialized scopes available in the market, iron sights might seem a far option for rifles.
It doesn’t mean to say we imply to not buy optics. Good optics come at a high price.
If it’s not a necessity or if you don’t have the budget for expensive optics, a good alternative would be iron sights to help you with every shot.
It’s always practical to know how to use guns in more than one way. As the saying goes, “It’s better to have it and not need it than need it and not have it,”.
This is a great skill to learn for any group of shooters – whether they do it as a hobby, hunting trips, or for a competition.
CHANGELOG: May 4, 2022 - Made minor updates to content September 16, 2021 - Reviewed and updated article links, updated article title