Range guide
How to Sight In a Rifle (Zero at 100 Yards)
Zeroing a rifle just means making the point of aim and the point of impact agree at a chosen distance. Done from a stable rest with a few careful groups, it is straightforward and repeatable. This guide walks the whole process — safety, getting on paper cheaply, reading a group, dialing the turrets in MOA, confirming at 100 yards, and logging the result — and shows how to record the whole thing as a range session so your zero is never a mystery later.
What you need
A good zero is mostly about removing variables. The more the rifle returns to the same spot between shots, the more the holes on paper tell you about the rifle instead of your hold. Bring:
The kit
One caution worth stating up front: your zero is tied to a specific load. Change the ammunition, and the point of impact can move, so confirm after any switch rather than assuming the old zero still holds.
The step-by-step process
Six steps. Read your group, move the impact toward your aim, confirm, and log it. The first step is the one you never skip.
- 1
Set up safely on a stable rest
Before touching the rifle, confirm it is unloaded, the action is open, and the muzzle points downrange in a safe direction with no ammunition in your work area. Wear eye and ear protection. Build a stable position: front and rear bags or a bipod plus a rear bag, so the rifle returns to the same spot between shots. A wobbly rest turns your zero into a guess, because you cannot tell rifle error from shooter error.
- 2
Get on paper cheaply first
Bore-sight the rifle or start at a short distance such as roughly 25 yards so your first shots actually hit the target. Bore-sighting (looking through the bore at a distant mark, or using a bore-sight tool) lines the barrel and optic up close enough to land on paper. Starting close means you waste fewer rounds hunting for your first hit before you can begin adjusting.
- 3
Fire a small group from the rest
Aiming at the same point every time, fire a small group of three to five rounds. Let the barrel settle between shots and break each shot cleanly. A single shot can lie to you; a group shows where the rifle is actually printing. Use the center of that group, not your best or worst hole, as the number you work from.
- 4
Measure center-to-aim and dial the turrets
Measure the distance and direction from the group's center to your point of aim. Convert that offset into scope adjustment. Most scopes adjust in MOA (minute of angle); one MOA is roughly one inch at 100 yards, and many scopes move 1/4 MOA per click, which is about 1/4 inch at 100 yards. Turrets are marked for direction (up/down, left/right). Dial the clicks needed to move the group onto your aim point — adjustments scale with distance, so at a shorter range each click moves the impact proportionally less.
- 5
Move to your zero distance and confirm
Once you are hitting close to point of aim up close, move the target to your chosen zero distance. For most centerfire rifles that is commonly 100 yards. Fire another group, measure center-to-aim again, and make a final small correction on the turrets. Your zero is set when the group's center sits where you are aiming at that distance.
- 6
Fire a confirmation group and log it
Shoot one more group to prove the zero holds, ideally including a cold-bore first shot from a clean, cool barrel — that is the shot that matters in the field. Record the ammunition, the distance, the final turret setting, and where the group landed. Logging it means you can return to this exact zero later, or notice when a bumped scope or a new load has shifted it.
Reading the group and dialing MOA
The whole adjustment step comes down to one habit: work from the center of the group, never a single hole. Find the middle of your cluster, measure how far and in what direction it sits from your aim point, and translate that into clicks.
Common mistakes
Log the zero in Rangium
A zero you cannot reproduce is only half a zero. Rangium turns a sighting-in trip into a record you can return to — the load, the distance, the turret setting, and the rounds you spent getting there:
Frequently asked
What distance should I zero at?+
It depends on the rifle and how you use it, but 100 yards is a common, practical zero for most centerfire rifles because it is easy to confirm and gives a predictable trajectory. Some shooters prefer other distances for specific purposes. Start on paper up close (around 25 yards) to get sighted in cheaply, then finish and confirm at your chosen distance.
What is MOA and how much does one click move?+
MOA stands for minute of angle, an angular measurement. One MOA is roughly one inch at 100 yards (about two inches at 200, and so on — it scales with distance). Many scopes adjust in 1/4 MOA per click, so one click moves impact about 1/4 inch at 100 yards. Always check your scope's turret markings, since some use 1/2 MOA, 1/8 MOA, or milliradian (MIL) adjustments instead.
How many rounds does it take to sight in a rifle?+
There is no fixed number, but a careful zero from a good rest often takes somewhere in the range of one to two boxes, depending on the rifle, optic, and how far off it starts. Bore-sighting first and starting close reduces the count. Fewer, well-aimed groups from a stable rest beat a large volume of hurried shots.
Do I need to bore-sight first?+
You do not have to, but it saves ammunition. Bore-sighting gets the barrel and optic roughly aligned so your first live rounds land on paper instead of missing the target entirely. If you skip it, just start at a short distance to get on paper before moving back.
Why re-confirm the cold-bore shot?+
The first shot from a clean, cool barrel — the cold-bore shot — can land in a slightly different place than shots fired once the barrel is warm and fouled. For hunting or any first-round-counts scenario, that first shot is the one you care about. Confirming it separately tells you where your rifle actually prints when it matters most.
Never lose a zero again
Start a 14-day free Pro trial and log your zeroing session, the load, and the rounds you spent — Rangium keeps the record and the running inventory so your next trip starts from a known zero. After the trial, Pro is $9.99/mo ($4.99/mo billed annually).