Reading Your Reticle: A Practical Guide to Subtensions

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Why We’re Doing This

This video kicks off a new series inspired by your questions—real-world shooters wanting clearer answers about the terminology we use every day. Whether it's MOA, BC, or in this case, subtensions, this series is designed to break things down in plain language, no fluff. I filmed this one live from one of our ranches, dust and all, just like we live it.

What Are Subtensions?

Let’s keep it simple:
Subtensions are the measurements inside your scope’s reticle.

• Each hash mark in your optic’s reticle represents a measured value, typically in MOA (Minute of Angle) or MRAD.
• Think of them as built-in rulers that let you measure and hold without dialing.

Example Using the Zeiss Conquest V4 (6–24x)

• This is a Second Focal Plane (SFP) scope.
• The subtensions (hash marks) are only accurate at full magnification—in this case, 24x.
• Each large and small hash mark in the reticle correlates with a specific MOA value.

Reading Subtensions in the Scope

Here’s how it plays out in the optic:

• Center Crosshair: 0 MOA
• Ends of the Crosshair: 1 MOA
• Next Large Hash Mark: 2 MOA
• Next Small Hash Mark: 3 MOA
• Continues in this pattern:
  • Large hash marks = even MOA values
  • Small hash marks = odd MOA values
• This reticle is designed for long-range hunting and shooting, featuring a tree-shaped crosshair with 1 MOA hash marks for precise holdovers and windage corrections. Only the center area is illuminated, providing a clear aiming point even in low-light conditions.‍
• For a more detailed view and specifications, you can refer to the official ZEISS datasheet:
  ZEISS ZBi Reticle Datasheet (PDF)

Why This Matters

• If you don’t want to dial or don’t have time, holding using subtensions is a quick and accurate method.
• You’ll use subtensions to adjust for elevation and wind on the fly.

Practical Use Case: Holding for Wind and Elevation

Let’s say:

• You’ve got a deer at 300 yards.
• Your rifle/ammo combo needs 4 MOA of elevation.

What to do:

1. Look through your optic at 24x.
2. Find the fourth subtension hash mark below center (big mark = 4 MOA).
3. Place that hash mark on your target.
4. Send it.

Same goes for wind:

• Wind from left to right? Push your aimpoint into the wind using the appropriate subtension.

You’ll often see me holding both elevation and wind at once. Example: 4 MOA up and 2 MOA right. No dialing needed.

Key Takeaways

• Subtensions are vital tools when you’re working fast or in dynamic conditions.
• They vary between optics—even within the same brand—so know your specific reticle.
• Check the manufacturer specs to understand what your subtensions represent.

Up Next in the Series

We’ll cover more shooting terminology you’ve asked about, like:

• Measuring group size
• Different ways to zero
• Other reticle and optic features

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