How to Zero Your Night Vision Scope: Complete Guide

Updated: Feb 9, 2026 | Read Time: 8 mins | Tested: AGM Spectrum 4K & Rattler V2

I’ve watched grown men argue on Reddit about whether you should zero a night vision scope during the day or at night. The answer? Both. And if you skip either one, you’re setting yourself up for missed shots and wasted ammo.

Here’s what nobody tells you: Your night vision scope’s point of impact will shift between day and night. Not because the scope sucks, but because of temperature changes, IR illuminator positioning, and how digital sensors behave differently than glass optics.

This isn’t theory. This is the step-by-step process I use to zero every NV scope I test, including the AGM Spectrum 4K and AGM Rattler V2. No fluff, no sponsored BS—just the truth from 200+ hours behind digital and thermal scopes.

WHY DAYTIME ZEROING ISN’T ENOUGH

I learned this the hard way with my first AGM Spectrum. I zeroed it perfectly at the range during the day—dead-on at 100 yards, nice tight group. That night, I set up on a feeder and watched a hog walk out at 120 yards. Centered the crosshair on the shoulder, squeezed… and missed clean over the back.

• What happened? Three things:
• IR Illuminator Offset: My IR light was mounted on the left side of the rail. During the day, I didn’t need it. At night, the IR beam created a parallax-like shift because the light source wasn’t perfectly aligned with the bore axis.
• Temperature Drop: It was 78°F when I zeroed. That night? 42°F. The scope housing contracted slightly, and my barrel’s harmonics changed. Not huge, but enough to shift POI by 1-3 inches at 100 yards.
• Focus Shift: At night, I had to adjust the digital focus to get a sharp image with IR. That internal sensor adjustment changed the reticle’s relationship to the target compared to daytime (where I used ambient light).

So yeah, if you only zero during the day, you’re gambling when it counts.

THE 2-STAGE ZEROING PROCESS

Here’s how to do it right. This is my exact process for digital NV scopes (AGM Spectrum, Sightmark Wraith, etc.). Thermal scopes follow the same principle.

Stage 1: Daytime Rough Zero (Bore Sighting + Confirmation)

You need a stable shooting platform. If you’re trying to zero off a wobbly tailgate, stop. Use a bench, sandbags, or a lead sled. I prefer sandbags because they don’t interfere with the rifle’s natural harmonics.

Step 1: Bore Sight (Optional but Smart)

If your scope has a visible laser bore sighter, use it. Saves ammo. I use a cheap $25 laser bore sighter from Amazon. Here’s the trick: don’t trust it to be perfect. Bore sighters get you “close”—usually within 6 inches at 50 yards. That’s good enough to get on paper.

Step 2: Fire a 3-Round Group at 25 Yards

Why 25 yards? Because if you’re way off, you won’t miss the entire target backer. I’ve seen guys start at 100 yards and waste 10 rounds trying to find where they’re hitting.

Fire three rounds. Slow and steady. If you jerk the trigger, you’re zeroing your bad shooting, not the scope.

Step 3: Adjust and Confirm

Measure the distance from your point of aim to the center of your group. Most NV scopes use 1/4 MOA or 1/2 MOA clicks. Check your manual.

• 1/4 MOA = 0.25 inches per click at 100 yards (roughly 0.06 inches at 25 yards)
• 1/2 MOA = 0.5 inches per click at 100 yards (roughly 0.12 inches at 25 yards)

• Elevation: 2 inches ÷ 0.06 = ~33 clicks UP
• Windage: 3 inches ÷ 0.06 = ~50 clicks LEFT

Make the adjustments. Fire another group. Repeat until you’re centered.

Step 4: Move to 100 Yards

Once you’re dialed at 25, back up to 100 yards. This is your “true zero” distance. Fire a 5-round group. Adjust as needed. Your goal: 1-2 inch group, centered on your point of aim.

Pro Tip: If you’re using a magnified NV scope (3-6x), zero at your highest magnification. The reticle stays fixed, but any optical imperfections are magnified too. Zeroing at max power ensures accuracy across all zoom levels.

Stage 2: Nighttime Verification & IR Zero

Now comes the part most people skip. Wait until it’s actually dark (not dusk—dark). You need to replicate hunting conditions.

Step 1: Set Up Your IR Illuminator

If you’re using an external IR light (like a Wicked Lights or Sniper Hog Light), mount it as close to the bore axis as possible. The farther off-axis your IR light is, the worse your parallax-style shift will be.

Here’s a dirty secret: even high-end scopes like the AGM Rattler can have a 1-2 inch POI shift at 100 yards if your IR is mounted on the far left of your rail. Physics doesn’t care how much you spent.

Step 2: Check Your POI at Night

Fire a 3-round group at 100 yards using only IR illumination. Do not touch your turrets yet. Just observe.

Common results I see:

• 1-2 inches low: Normal. Cooler temps + barrel harmonics.
• 1-3 inches left/right: IR illuminator offset. The beam is hitting the target from an angle, creating a perceived shift.
• 4+ inches off: Something’s wrong. Check your rail, scope rings, or IR mount. Something shifted.