How to Sight In a Thermal Scope

Sighting in a thermal scope is a little different from a regular optic, and easier once you understand the freeze-zero approach most thermals use. You will need a heat-contrasting target so the scope can actually see your aim point and your hits.

Here is the step-by-step.

The Short Answer

Use a heat-contrasting target (a hand warmer behind the bullseye works) and the freeze-zero method most thermals use: fire one careful shot from a solid rest, freeze the image while holding your aim point, move the reticle to your actual bullet hole, save, then fire a confirming shot.

Set Up a Target It Can See

Thermal sees heat, so a paper bullseye is invisible. Use a target with thermal contrast: a hand warmer behind the bullseye, a metal target that holds heat, or a purpose-made thermal target. Set it at your chosen zero distance, commonly 50 or 100 yards.

Get the rifle steady on a solid rest. A bag or bipod and a calm position make this far easier.

The Freeze-Zero Method

Most thermals use a one-shot freeze zero:

Aim center and fire one careful shot.
Without moving the rifle, enter the scope's zeroing mode and freeze the image.
Keep the reticle on your original aim point and move a second marker to your actual bullet hole.
Save. The scope shifts the reticle to match your point of impact.

Fire a confirming shot. You should be dead on, or close enough to repeat once.

Confirm and Record

Shoot a small group to confirm the zero holds, then record your settings. If you run a clip-on instead, your daytime scope keeps its zero; see our clip-on guide. Recheck zero any time you remount or travel.

One-Shot vs. Multi-Shot Zero

There are two ways to get zeroed, and most thermals support both:

One-shot (freeze) zero is the fast field method above: fire once, freeze the image, and drag the reticle onto the hole. You are usually dialed in within three to five rounds.
Multi-shot zero is the precision method: fire a three to five round group, measure the offset from your aim point, and adjust until centered. It uses more ammo but averages out a flyer.

Use one-shot to get on fast or re-zero in the field, and a confirming group before a hunt.

If Your Zero Won't Hold

If point of impact wanders, work through the usual suspects before blaming the scope:

Run a calibration (NUC) before shooting a group so the sensor shows a clean image.
Zero at base magnification, not on digital zoom, so your reference is the true image.
Check the mount first. Loose ring screws and an under-torqued base are the most common cause of a moving zero.
Re-confirm after any change: a new ammo lot, a remount, a hard knock, a firmware update, or a big seasonal temperature swing can all shift things.

FAQ

Common Questions

How do you sight in a thermal scope?

Use a heat-contrasting target at your zero distance, fire one careful shot from a solid rest, then use the scope's freeze-zero mode to move the reticle to your bullet's point of impact and save. Confirm with a follow-up shot.

What target do you use to zero a thermal scope?

A target with thermal contrast, such as a hand warmer behind the bullseye, a heat-retaining metal target, or a purpose-made thermal target. A plain paper bullseye is invisible to thermal.

What is freeze zeroing?

Freeze zeroing lets you fire one shot, freeze the image while holding your original aim point, then move the reticle to your actual bullet hole and save. It zeros most thermals in a shot or two.

What distance should I zero a thermal scope?

Common zero distances are 50 or 100 yards, matched to your typical shooting range. Choose the distance where most of your shots happen and confirm holdovers from there.

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Thermal scope specifications, prices, and model availability change frequently. This guide is for general reference only. Confirm current specs and pricing on the product page before you buy.

Hunting with thermal optics is legal in some states and seasons and restricted in others, especially for big game. Always verify your state and local regulations before hunting with a thermal scope. Double D Hunting is not responsible for errors, omissions, or decisions made based on this information.