A three-pin sight is set in order, not all at once. Zero the top pin at your closest working distance and get it truly centered, then walk back and set the middle and bottom pins using only their own vertical adjustment. Move the whole housing when every pin is off in the same direction, and move a single pin only when that one distance is wrong.
This post assumes you already own a multi-pin sight, you can hold a group, and you want the stack itself sorted. If you are starting from a bare bow and a fresh sight, work through the general process in our guide to how to sight in a compound bow first, then come back here for the pin stack.
What the pin stack is really doing
Each pin is a fixed aiming point that matches one arrow drop. The arrow leaves the bow and immediately starts falling, so to hit something further away you have to tilt the bow up a little more. Rather than guess at that tilt, the sight gives you three reference points stacked vertically, and you pick the one that matches the range.
The important consequence is that the pins are not independent of each other. They all share one housing, one mounting bracket and one sight bar. Anything that shifts the housing shifts all three pins together and by the same amount. Anything that changes how fast your arrow leaves the bow changes the distance between the pins without moving any of them. Understanding which of those two things you are looking at is most of the skill.
That is also why the top pin comes first. The other two are set by moving back and correcting for the drop you observe, so they inherit any error in the top pin. Set it approximately and you will chase the stack all afternoon.
Before you touch a pin
Ten minutes of checking saves an afternoon of confusion. A loose sight bracket produces exactly the same symptom as bad form, and you cannot tell them apart from behind the string.
- Check the sight mounting bolts against the riser and the bracket screws that hold the housing. Snug and even, not overtightened.
- Inspect the string and the cables for fraying, separated strands, serving separation or a peep that has rotated. A string that is on its way out will not hold a zero, and it belongs in front of a technician.
- Confirm the peep sits where it should at full draw without you craning your neck to find it. If you are hunting for the peep, you are also hunting for the pin.
- Sort your arrows. Same spine, same length, same points, same fletching orientation, same nocks. Retire anything with a cracked nock or a damaged shaft.
- Check that every point and insert is tight. A loose point walks a group and looks precisely like a sight problem.
Never dry fire a bow, not once, not to see what happens, and not to unload it at the end of a session. A dry fire can destroy limbs and injure the shooter. Inspect the string and cables before every session and stop shooting if anything looks wrong. Use a target rated for the speed you are shooting, set on a backstop that will hold a pass through, and know what is behind it. Broadheads stay in the quiver until you are deliberately testing them on a broadhead-rated target.
Set the top pin first, and set it properly
Work from a solid stance you can repeat, or from a stool if you shoot seated in the field. The goal is to take your own wobble out of the picture so that the holes on the target are telling you about the sight and not about your day.
- Get on paper close
Start much nearer than your intended top pin distance. A big aiming point on a big backer means a wild first arrow still leaves a mark you can measure from. You only need a rough idea of where the bow is printing.
- Move the housing to close the coarse error
At this stage the whole stack is off, so move the housing, not the individual pin. Chase the arrow, meaning move the sight in the same direction the group landed relative to your aiming point.
- Step back to your chosen top pin distance
Shoot three arrows at the same spot. One arrow is an anecdote. Three is information.
- Correct windage first, then elevation
Work from the center of the group rather than your best arrow. Fixing one axis at a time stops you from over-correcting both and ending up somewhere new.
- Confirm with a fresh group
Shoot three more without touching anything. If the group is centered, stop. Adjusting toward individual arrows is the single fastest way to lose a zero you already had.
- Only now go to the second pin
Leave the housing alone from this point. The middle and bottom pins are set by sliding those pins alone.
Windage deserves a note. On most sights, once the top pin is centered horizontally the other two are close to correct already, because they sit on the same vertical line. If your lower pins want a very different windage, that usually points at arrow tuning or torque rather than the sight, and it is worth resolving before you keep going.
Moving the housing versus moving one pin
This is the decision people get wrong most often, and it has a simple test. Ask whether the error is the same at every distance or specific to one distance.
| What you are seeing | Most likely cause | What to move |
|---|---|---|
| All three pins print left or right by a similar amount | Windage of the whole sight, or a shifted peep | The housing, in windage. Check the peep before you turn anything. |
| All three print high or low by a similar amount | Something global changed, such as anchor, peep height or arrow weight | The housing, in elevation, then re-confirm the top pin |
| Top pin is dead on, lower pins are off | Arrow speed differs from what the stack was set to | The individual lower pins, one at a time |
| Only one pin is off, the two either side are fine | That pin has crept in its slot | That pin alone. Then check its lock screw. |
| Pins move between sessions on their own | Loose pin lock screws or a loose housing bracket | Nothing yet. Tighten, re-verify, then re-set what actually moved. |
Scroll the table sideways to see every column.
The habit worth building is this. Housing adjustments are for global problems. Individual pin adjustments are for one distance. If you find yourself moving the housing after the top pin is set, stop and work out what changed, because you are about to undo the pin work you have already done.
Pin gap and what changes it
The vertical distance between your pins is not a setting you choose directly. It is the result of how much your arrow drops between the two distances those pins cover, which in turn depends on how fast the arrow is leaving the bow and how much it weighs. You set the pins where the arrows land, and the gap is whatever it turns out to be.
What that means practically is that gaps get bigger as you go down the stack. The arrow is falling faster later in its flight, so the last stretch of range costs more elevation than the first. Expect the space between your middle and bottom pins to be noticeably wider than the space between your top and middle. That is normal and not a sign anything is wrong.
Things that change the gap without you touching a pin include a change in arrow weight, a change in point weight, a change in draw weight, a new string, a different draw length, or fletching that adds drag. Any of those and the stack needs re-verifying, not just the top pin.
Tighter gaps
- Pins crowd the target at longer range, which can obscure the vitals
- Less housing space used, so a fourth pin or a wide top gap fits more easily
- Small aiming errors between pins matter less because the pins are closer in value
Wider gaps
- Easier to tell the pins apart quickly in low light
- More room to gap-shoot the space between two pins for an in-between range
- Runs out of housing sooner, which limits how far the bottom pin can reach
Neither is better. A gap is a readout, not a goal. If yours are so tight that you struggle to pick the right pin under a canopy at first light, that is worth solving with pin size, brightness and pin order rather than by chasing the gap itself.
Choosing which distances your three pins cover
Three pins is a deliberate constraint, and the right answer depends entirely on where you hunt. Start from the shot you actually expect to take, not from what looks impressive on paper.
If most of your shots come from a stand over a trail or a feeder, the useful ranges cluster close and the spread between them is small. Setting your three pins across a narrow band gives you fine resolution exactly where the animal will be, and you accept that anything beyond the bottom pin is simply not your shot. If you spot and stalk in open country, the same three pins spread wider make more sense, and you give up some precision at the close end to gain reach.
Two guidelines hold up across both cases. First, the top pin should cover the range you are most likely to shoot at, because that is the pin you will pick under pressure and the one you have practiced with most. Second, the bottom pin should sit at a distance where you can still hold a group you would be willing to take at a live animal, on a day with wind, in hunting clothes. Setting a bottom pin further than your honest ability just puts a temptation in the housing.
Write the distances down and tape the card somewhere you will see it. The pin you cannot name under pressure is the pin you will not use. The same discipline applies across platforms, whether you are working a crossbow reticle stack or a scope on a rifle.
Re-checking the stack after any change
The stack is a record of one specific setup. Change the setup and the record is out of date. Draw weight is the obvious one, because turning the limb bolts changes arrow speed and therefore every gap in the stack, but arrow weight, point weight and a new string all do the same thing to a lesser degree.
The efficient way to re-verify is to check the top pin first. If the top pin is still centered, your global geometry is fine and you only need to walk the lower pins. If the top pin has moved, fix that with the housing before you look at anything below it, otherwise you will correct the lower pins for an error that lives at the top.
Re-check before the season opens, after travel, after the bow gets knocked over, and any time you swap arrows or points. A three-arrow group at your top pin distance answers the question in a few minutes and is the cheapest insurance in the sport.
Record the date, your draw weight, arrow and point weight, the three pin distances and where each group landed. Next season, that card tells you instantly whether something drifted or whether you are just shooting differently. Photograph it so you have a copy on your phone.
Broadheads deserve their own confirmation once the stack is set. Verify with the exact heads you will hunt with, on a broadhead-rated target, starting at your top pin distance and working down the stack. If they land somewhere else, check arrow straightness and insert alignment before you start moving pins.
Carrying the bow to the stand is its own problem, and the same is true of every long walk in with a firearm. If you also take a rifle out in the same season, our notes on a rifle sling for hunting cover hands-free carry on rough ground, and the McLean Dynamic Retention Sling uses a patented two point to one point conversion with maritime grade webbing and all metal hardware. If you need a second attachment point to make that work, our quick detach sling mounts cover the common conversions.
Working on other platforms this off season? The same order of operations applies with different constraints in our posts on sighting in an air rifle and sighting in a muzzleloader, and if you are teaching someone from scratch, start them on sighting in a bow and arrow instead.
Frequently asked questions
Which pin do I set first on a three-pin sight?
The top pin, at your closest working distance. The middle and bottom pins are set by moving back and correcting for observed drop, so any error in the top pin is inherited by both of them. Get it centered with a confirmed three-arrow group before you touch anything below it.
Should I move the whole sight housing or just one pin?
Move the housing when all three pins are off in the same direction by a similar amount, because that is a global problem such as windage, peep height or a changed anchor. Move a single pin when only that one distance is wrong. After the top pin is set, you should rarely need the housing again.
Why is the gap between my bottom two pins so much bigger?
Because the arrow is dropping faster later in its flight, so the same jump in distance costs more elevation down the stack. Widening gaps toward the bottom are normal. A gap that changes between sessions is not, and usually means arrow weight, draw weight or the string has changed.
Do I need to re-sight after changing draw weight?
Yes. Draw weight changes arrow speed, which changes the drop between every pair of pins. Check the top pin first. If it is still centered, walk the lower pins one at a time. If it has moved, correct with the housing before you look at anything below it.
