How MOA Relates to Scopes & Optics

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Guide 01 · Chapter 04 · Understanding MOA · 4.3

How MOA Relates To Scopes & Optics

Many riflescopes use either MOA or MRAD for their turret adjustments and reticle measurements. Neither system is inherently more accurate than the other — they're simply two different ways of measuring the same angular relationship. What matters most is understanding the system your optic uses and, ideally, having your turrets and reticle measured in the same unit.

Shooter adjusting the elevation turret on a precision riflescope mounted to a bolt-action rifle.

What Does "MOA Per Click" Mean?

Every tactile click on an MOA turret represents a specified angular adjustment. Common values are ¼ MOA and ⅛ MOA per click, though other increments exist depending on the manufacturer. Always check the markings on your own turret and the manufacturer's specification sheet before assuming a value — this is one of the most common sources of adjustment errors.

A ¼-MOA Turret

On A ¼-MOA Turret

Four clicks equal 1 MOA
One click moves point of impact approximately 0.262 inches at 100 yards
One click moves point of impact approximately 7.27mm at 100 metres
Because MOA is angular, the physical distance one click represents changes with range — a click is worth less at 25 yards than it is at 100

It's worth being precise here: four ¼-MOA clicks equal 1 MOA, which is approximately 1.047 inches at 100 yards — not exactly one inch. That small difference is negligible at short range but compounds as distance and the number of clicks required increases.

Scope-Adjustment Reference Tables

These are the approximate linear values represented by common MOA increments at typical zeroing and adjustment distances.

Increment (Imperial)	25 Yards	100 Yards
1 MOA	0.262 in	1.047 in
½ MOA	0.131 in	0.524 in
¼ MOA	0.065 in	0.262 in
⅛ MOA	0.033 in	0.131 in

Increment (Metric)	25 Metres	100 Metres
1 MOA	7.27 mm	29.09 mm
½ MOA	3.64 mm	14.55 mm
¼ MOA	1.82 mm	7.27 mm
⅛ MOA	0.91 mm	3.64 mm

These are approximate linear subtensions of each angular increment at the stated distance — not fixed physical measurements independent of range.

How To Calculate A Zero Correction

Step 1

Fire a properly controlled group — a single shot doesn't tell you enough to adjust from.

Step 2

Measure the centre of the group relative to your intended point of impact.

Step 3

Convert the required horizontal and vertical movement into MOA.

Step 4

Convert the MOA correction into clicks using your turret's click value.

Step 5

Dial carefully in the direction indicated by the turret markings.

Step 6

Fire another group to confirm the correction landed where you intended.

The group's centre — not the position of any single shot within it — should guide the adjustment. Chasing an individual flyer will lead you to correct for something that isn't actually a zero problem.

Metric Worked Example

100 Metres Group centre is 58mm low at 100 metres 1 MOA at 100 metres is approximately 29.1mm 58 ÷ 29.1 ≈ 2 MOA On a ¼-MOA turret: 2 MOA × 4 clicks per MOA = 8 clicks

Turn the elevation turret eight clicks in the direction marked "UP." This applies an upward correction of approximately 2 MOA to the subsequent point of impact.

Imperial Worked Example

100 Yards Group centre is 2.1 inches right at 100 yards 1 MOA at 100 yards is approximately 1.047 inches 2.1 ÷ 1.047 ≈ 2 MOA On a ¼-MOA turret: 2 MOA × 4 clicks per MOA = 8 clicks left

Same process, same logic, just worked in inches and yards instead of millimetres and metres.

Windage And Elevation

The Two Axes

Elevation corrections move the intended point of impact vertically — compensating for bullet drop or a high/low zero
Windage corrections move it horizontally — compensating for wind drift or a left/right zero
Turret directions must always be checked on the turret itself, never assumed from memory or from another optic
The correction required depends on both the distance to target and the size of the angular error observed or calculated

Turret And Reticle Matching

An MOA turret paired with an MOA reticle is the easiest combination to work with. If you observe an error directly through a properly understood MOA reticle — say, a group sitting 2 MOA left of centre in the reticle's own hash marks — you can often dial that correction straight in without ever converting from centimetres or inches at all. Ideally, the turret adjustments and reticle subtensions should use the same angular unit.

First Focal Plane & Second Focal Plane — A Caution

Briefly: a first focal plane (FFP) reticle's subtensions stay accurate at any magnification setting, because the reticle grows and shrinks along with the image. A second focal plane (SFP) reticle is generally only accurate at one specified magnification — usually the top of the zoom range — and its measurements become unreliable elsewhere. Always confirm which type your optic uses and check the manufacturer's reticle manual before relying on reticle measurements for a correction. We'll cover reticles properly in a dedicated module.

Mechanical Limitations And Verification

Worth Knowing

Turret adjustments have finite travel — you can run out of elevation or windage before you run out of distance
Not every optic tracks perfectly; some drift slightly from their stated click value over their adjustment range
Loose mounts, inconsistent shooting technique, parallax error, or a genuinely unstable group can all mimic what looks like an adjustment problem
Every calculated correction must be confirmed by actually firing it under safe, controlled range conditions — the maths gets you close, live fire tells you if it worked

Common Mistakes

Watch Out For

Mixing metres and yards within the same calculation
Using rounded Shooter's MOA where an exact calculation was needed
Assuming every turret clicks in ¼ MOA without checking
Adjusting off a single poor shot instead of a proper group centre
Dialling the correction in the wrong direction
Confusing an MOA turret with an MRAD reticle, or vice versa
Using second-focal-plane reticle subtensions at the wrong magnification
Confusing the mechanical movement of the reticle inside the scope with the intended movement of the point of impact on target