How to Zero Your New Sight¶

Franco’s hybrid method to use as few rounds as possible

So you just got a new optic or gun and want to sight in but you’re not sure how and you’re feeling a little overwhelmed. This guide that breaks everything down into simple steps can help!¶

Step 1: Select Your Zero Distance¶

If you’re interested in understanding WHY a given zero distance makes sense, here’s a breakdown going into the concepts that affect zero distance. We’re avoiding math in this section - if you want a really nerdy deep-dive, there’s a lot of guides out there on the internet! Arithmetic will be useful later but none is required for this section. But if you want to pick a zero distance and know why you’re picking that, reading this section may help!

Q: My setup is normal and I’m not really interested in nerding out¶

A: Zero your rifle at 50 yards and your pistol at 15 yards. Skip to the last question in this section.

Q: Why does zero distance matter?¶

A: Because of bore offset! WTF is bore offset? It’s the vertical offset between the center of your sight and your barrel. This means that if your sight and your barrel are perfectly aligned and parallel, there will actually be a gap between where your sights are and where the bullet goes! Check out the diagram below for a visual.

All guns have bore offset but the amount of bore offset varies. Even pistols have bore offset, but they are typically quite a bit lower than most rifles. In fact, even iron sights have bore offset. If you’re not looking straight through the barrel, you’re gonna be dealing with some kind of offset. A typical pistol with irons has about a .5” bore offset. With a red dot this increases to about 1”, whereas a typical AR-15 has about a 2.5” bore offset. So… why does this affect zero distance? And what zero distance does this mean I should pick? We’ll get there, but first…

Q: Ok, so how is it even possible to hit where you’re aiming?¶

A: Simple! Just adjust your sight so that it’s angled down ever so slightly! The distance at which the sight and bullet cross is your zero distance. Done.

Q: OK, hmm, then how does the bullet not go up forever after crossing your zero?¶

A: Because bullets don’t travel in a straight line. From the moment the bullet leaves the barrel it starts dropping, but not fast enough to not cross the sights at your zero distance. If you set your zero distance well, the bullet trajectory will top out and start dropping before it goes too far above your sights, then eventually drops under your sights again. This is why choosing your zero distance to suit the ballistics of your gun as well as your height over bore matters - if you get it wrong you might find that you have a really big gap between where you aim and where your bullet hits at certain distances. Choosing well results in a good “battle zero” where your bullet hits very close to where you’re aiming over a really broad range of distances. Below is a diagram showing what happens when you zero to a good “battle zero” distance

Q: Ok I mostly get it! So what does that actually mean about choosing my zero distance?¶

A: If you logic this out a bit, what this means:

Fast bullets should have a farther zero distance over slow bullets, because fast bullets will rise too high above your point of aim if you zero too close.
Higher height over bore should have a farther zero distance than lower. Otherwise your sight is angled down too much and again, your bullet rises way above your point of aim.

Since pistols have low height over bore and slow bullets, that generally means you want to zero your pistol at a much closer distance than your rifles. A typical zero distance for a pistol is 15-25 yards, whereas a typical zero distance for a rifle is 50-100 yards. And now that you understand why, you can make a smart decision for your own setup! For example, if your rifle fires a slow bullet (for a rifle), such as 300 blackout, maybe you bump your zero distance inwards to 40ish yards. If you have a very tall sight though, like an AK with a red dot on a riser (about 4 inches over bore), you might consider bumping your zero out farther towards 100 yards to keep a tighter spread between aiming point and bullet. Same for a pistol - a pistol with a very tall red dot or a fast cartridge such as 5.7 might warrant a farther zero distance like 25 yards, but if you’re adjusting low irons maybe closer in like 10 yards is just fine.

Keep in mind that this explanation only just scratches the surface of this topic. If you want to learn more there’s tons of amazing in-depth guides, but I think at this point we’ve learned more than enough to achieve a good first-ever zero.

Q: Ok got it, I think I decided on a zero distance but my range doesn’t go that far!¶

A: Infinite zero targets! You can use their site to make and print a custom target that gives you a point of aim and a point of impact to adjust to for whatever the longest distance that you’re able to actually shoot is. The guide on their website is really good - just check out their guide and make your own custom target. https://www.infinitezerotargets.com/

Step 2: Building a zeroing position¶

You don’t need to have godlike marksmanship to zero your optic! You just need to build up a position that takes as much human error out of the equation as possible. This means you should be supporting your gun with a bag seated on a bench, or prone if possible. No standing shots unless you’re supremely confident in your marksmanship! This remains the case for pistols - you should be using a bag support if you really want your group to be as good as possible. Most ranges have bench rests and/or sandbags available for rent - definitely take advantage of this if you don’t have your own!

Rifle Position¶

For a rifle, the only hard requirement is that you do something to support the handguard. This can be done one of three ways: a bench rest, a sandbag, or a bipod. If your rifle has a bipod, use that. Otherwise, a bench rest or a sandbag are equally good options. A rear sandbag is not required but is very nice to have - if you are able to support the stock such that the rifle mostly stays on target with just very light pressure, that is the most stable possible position.

Last note on this - many people find prone to be the easiest position to be accurate with. However, many ranges do not allow prone shooting - if you can’t, shooting seated off a bench is fine!

Pistol Position¶

It sounds silly, but zeroing your pistol supported is even more important! It’s even harder to avoid moving a pistol while pulling the trigger standing than it is a rifle - supporting the pistol makes this waaay easier. For pistol, the supported position is straightforward - seated, hand or bottom of the grip on the bag and make sure to maintain your grip while doing this!

Finding an accurate sight picture¶

You want to make sure to find the most accurate possible sight picture for the best possible groupings. This varies by the type of sighting system you’re zeroing - for iron sights, you should be keeping the front sight in focus with the target slightly blurry. For red dots, just focus on the target for the sharpest possible dot. And for scopes, the reticle and target should be sharply focused to each other - if not, your scope may have a parallax adjustment that you need to match to your chosen zero distance.

Note on the trigger pull¶

When zeroing supported, there is no such thing as too slow of a trigger pull. Since you won’t be getting tired from holding the gun up, just take your time and pull that trigger SLOW! If you pull it so gradually that it surprises you when the gun goes off, that’s a good thing! This will make your zeroing journey much easier.

Step 3: Understanding Installation and Adjustments¶

Before you zero, you have to know how to set up and adjust your sights. I’ll also cover installation VERY briefly. This won’t be an installation guide, just a few tips and pointing you towards resources to install your specific optic.

A few words on installation¶

Installing your optic properly is extremely important! If installed improperly, your optic will come loose or shift and all your hard work zeroing will be lost. For direct mount red dots, make sure to use appropriate torque as well as thread locker. Make sure to wait long enough for the thread locker to cure before heading to the range. For a scope with rings, make sure to follow the manufacturer’s recommended torque specs, leveling procedure, and installation order. For an excellent video guide on how to install a generic scope, check out Vortex’s guide:
https://www.youtube.com/watch?v=FmHp5TgkD0w

Adjustment Coarseness¶

Different sights have different amounts of coarseness of their adjustments. The “coarseness” of a sight’s adjustment means how much the sight moves per click of adjustment. This is expressed in angle, either Minute of Angle (MOA) or Milliradians (Mil). It’s not really important to know exactly what each of these units are, but we’ll go over how much you’re actually moving the sight in a later section. In general, the coarseness of the adjustment matches the use case of the sight. Pistol sights generally have coarser adjustments that move the sight farther per click than a high magnification riflescope. The coarseness typically varies from 1 MOA per click to .25MOA per click. To verify what coarseness your exact setup has, the adjustment is often written on the adjustment screw/turret, or in the user manual.

Optic Adjusters¶

Optics use either screws or turrets for adjustment. Elevation (up/down) adjustment is typically on top, and windage (left/right) adjustment is typically on the right side. The majority of adjusters will have an arrow indicating “RIGHT” on the windage adjuster and “UP” on the elevation adjuster. These adjusters move the bullet up/right, not the sights. When you see the holes in your target, use the indicated directions as a guide on the direction that you want the holes to move rather than the reticle of the sight.

Red Dots¶

Red dots typically have adjustment screws. These screws can be flat head, hex, or torx. They typically click when turned, but some do not and have separate lock screws.

Some rifle red dots have tiny turrets rather than screws. To adjust these, remove the cap and turn the turret either with your fingers or with the adjuster tool built into the cap.

Riflescopes¶

Riflescopes (LPVOs included) have adjustment turrets, with the same layout as red dot adjusters. The turrets are usually marked with the adjustment that the scope is currently at, and these markings can themselves be adjusted so that the 0 on the turret aligns with your rifle’s zero once you’re sighted in. Every manufacturer has a different method of setting this zero value, so I can’t cover all the different methods of setting the turret zero in this guide. Your scope’s manual will include all of the instructions for setting the turret to zero. Scopes have three types of turrets: Exposed, Locking, and Capped. If your scope’s turrets do not have any visible numbers on them, that usually means they are capped. To access and adjust your turrets, you’ll have to unscrew the cap to reveal the turret adjuster underneath. Below is an example of capped turrets:

If your scope’s turrets have visible adjustment markings, you have either exposed or locking turrets. If your turrets can be turned by hand with no extra steps, they are exposed turrets. If they don’t budge, try pulling up firmly on the turrets - this will unlock the turret and allow it to turn if it’s a locking turret. Below is an example of what an exposed or locking turret looks like:

Note that many scopes have a combination of an exposed or locking elevation turret and capped windage turret.

Rifle Irons¶

Rifle irons have an almost infinite variety of adjustment mechanisms. For the purposes of this guide, we’ll just cover the most common adjustment mechanism, found on most M16/M4 iron sights, most backup iron sights, and a variety of other rifles. If your sights are a different system, you’ll have to look up the adjustment mechanism for your particular rifle. For windage on M4 style iron sights, there is a knob on the right side of the rear sight that works similarly to the windage knob on a scope turret. This changes the sight alignment by moving the aperture side to side. For elevation, you have to use either a bullet tip or a special tool to screw the entire post in and out. I highly recommend you invest in the tool, as adjusting with a bullet tip or other improvised tool is a big pain. This changes sight alignment by moving the post up and down. Some backup irons have a knob under the front sight, in which case they can be adjusted without tools by turning the knob. Below is a photo of toolless adjustment controls on backup iron sights:

Here is a front sight post adjustment tool being used to adjust elevation on M4-style sights:

Pistol irons¶

Pistol irons also have a wide variety of adjustment methods, but there is a system that is by far the most common that we can cover here. Note that the second-most common system is fixed sights with no adjustment, so unless something is wrong with your pistol, those should be dead on from the factory! The most common pistol iron adjustment is a locking dovetail. To adjust these, you need to have a pistol sight pusher tool. First, loosen the locking screw on the rear sight (some don’t have a locking screw, in which case skip this step), then clamp the slide in the sight pusher tool, and slowly push the rear sight notch in the same direction that you want your bullet impacts to move. Once you’ve achieved the sight alignment you want, make sure to retighten the locking screw! These sights typically have no elevation adjustment - elevation is fixed from the factory.

A note on adjusting your pistol irons - is it the gun shooting low left?¶

The vast majority of pistols have very well adjusted sights from the factory - it’s very rare to need to adjust your iron sights! If your groups are off from where you’re aiming, you want to be sure it’s the sights that are off rather than you moving the pistol unintentionally as you pull the trigger. Many new shooters feel that their sights are off and that causes them to hit low left. Ultimately, 99% of the time, groups going low-left is due to the shooter pushing against the recoil as the trigger is pulled. It’s very rare that adjusting the sights is the fix for this rather than working on technique. If you believe your irons are off, make sure to verify by having an experienced shooter shoot a group, preferably while supported by a bag, and only make adjustments if their group position is off in the same way yours is.

Q: Ok, I know how to adjust my optic, but how do I know how many clicks will actually get me to the center?¶

With math! We can use a simple trick for this - at 100 yards, one MOA is almost exactly one inch. So if you’re shooting at 100 yards with a scope that has .25 MOA clicks and your bullet lands two inches right of the target, you can just give it 2”÷.25MOA = 8 clicks left.

If you have a riflescope that uses Mils/MRAD, instead of 1 inch at 100 yards, it instead measures 1/1000^th of the distance you are shooting at. If you're shooting at 100 meters, then a MIL is 100mm. Mils usually adjust in terms of a tenth of a mil, so .1 MIL (one click) at 100m is 10mm or roughly .4 inches. If you're shooting at 100 yards, then a full MIL is .1 yard or 3.6 inches. This means that .1 MIL (again, one click) is .36 inches"

Q: But what if I’m not zeroing at 100 yards?¶

This rule also scales linearly with the fraction of the distance to 100 yards that your target is at. What does that mean? It just means that if your target is at 50 yards, (half the distance), for that same .25 MOA scope, 2”÷.25MOA÷.5(x of 100yd)= 16 clicks left to move those same two inches. Inverting that, at 200 yards, to move your impact two inches, you do the same math: 2”÷.25MOA÷2(x of 100yd) = 4 clicks left. Here’s some “scenarios” to hopefully help you make more sense of this!
Pistol Red Dot: 1 MOA Per Click
Zero Distance: 10yd
Group Center: 1.5 inches low and 2 inches right
1.5”up ÷ 1MOA ÷ .1(x of 100 yd) = 15 clicks up
2”left ÷ 1MOA ÷ .1(x of 100 yd) = 20 clicks left

PCC Red Dot: .5 MOA Per Click
Zero Distance: 25yd
Group Center: 2.5 inches high, 1 inch left
2.5”down ÷ .5MOA ÷ .25(x of 100 yd) = 20 clicks down
1”right ÷ .5MOA ÷ .25(x of 100 yd) = 8 clicks right

Rifle Scope: .25 MOA Per Click
Zero Distance: 50yd
Group Center: 1 inch high, 4 inches right
1”down ÷ .25MOA ÷ .5(x of 100 yd) = 8 clicks down
4”left ÷ .25MOA ÷ .5(x of 100 yd) = 32 clicks left

Q: Is there a way to do this without the math?¶

Sort of - you can guesstimate how many clicks you’ll need and try shooting another group. If you end up zeroing stuff often, eventually you’ll get an intuitive sense of how many clicks you need to use to get to the center, but this method will always waste more time and ammo, especially early on in the learning process.

Step 4: Steps for actually doing the zero¶

Here is a three-part process for actually getting the zero set at the range. I strongly suggest you bring multiple targets - it’ll be much easier to track where your hits are going if you swap to a fresh target between each section.

One last thing before getting started - when you determine a number of clicks to adjust to, it’s a great idea to write that down before making the adjustment. This will help you make more sense of whether your adjustment size was the right one or not, and also will help you more easily reverse an adjustment accidentally made in the wrong direction.

Part 1: Getting on paper¶

There are various methods and products that help you get a close enough optic alignment to make sure you don’t miss the paper entirely when you zero - however, as long as you have access to a range that allows a variety of target distances, you shouldn’t need to use any of those products. If you start with the target very close up, you can be guaranteed to hit even a sheet of letter paper. A good starting distance is 5 yards for pistol and 10 yards for a rifle or PCC. In order to ensure we stay on paper, we can then adjust our optic so that the bullet hole matches roughly our height over bore under the center of the target.

Steps:¶

Start at 10yds for rifle, 5yds for pistol
Take one shot and verify you’re on paper
Make gross windage adjustments to attempt to roughly center windage
Make gross elevation adjustments to attempt to roughly match height over bore
Repeat Steps 2-4 until you make a hole close to centered at height over bore. Now you’ll be on paper at a farther distance!

Part 2: Achieving a rough zero¶

Once you’re confident you’ll be on paper when you’re a little farther out, the next step is to dial in a rough zero. A good distance for this step is 10 yards for pistol and 20 yards for rifle. We’ll also be shooting more than one round, since the random dispersion that all guns have could cause a single round to be misleading when trying to refine point of impact. If you’re only going to be shooting at short ranges, dialing in a rough zero is good enough in a pinch!

Steps:¶

Move target to 10yds for pistol, 20yds for rifle
Take one shot
Verify hole is roughly centered on windage and close to but around .5 inch below center for pistol, about 1 inch below center for rifle
Repeat Steps 1-3 until a hole where you want appears
Shoot a three-shot group and verify that the center of the group is where you want it. If not, adjust and shoot another group
Rough zero achieved!

Part 3: Achieving a final zero¶

After you have a rough zero, you can refine your zero to its final distance. We’ll be shooting 5 round groups to increase our confidence that our group really is centered where we think.

Steps:¶

Move the target to the final zero distance
Shoot a five-shot group
Adjust your sights to move the center of your group to the center of the target
If ammo is tight, just use the math from Step 2 to adjust your group to be centered and call it good! If not, shoot another five-shot group to verify your adjustment.
Precise zero achieved!

That’s it! If you have additional questions, don’t hesitate to ask our coaches in our Discord!