IRON NEST Calibration Fire Explained: First-Shot Setup and Fixes

The first Calibration Fire tutorial in IRON NEST: Heavy Turret Simulator can be surprisingly confusing. Rather than simply telling you where to aim, the mission introduces several different stations and expects you to connect the entire firing process yourself.

I struggled with this first tutorial, so this guide breaks down the solution that worked in my playthrough.

Calibration Fire Quick Solution

For the order shown in the video:

Setting	Value
Iron Nest position	H3 5:5
Target	Q4 4:2
Bearing	85.4°
Range	8.90 km
Shell	HE
Powder charges	2
Left-gun elevation	53.40°
Gun	Left

1. Plot the Shot Correctly

Start by reading the full High Command order.

Place the Iron Nest marker at H3 5:5 and the target at Q4 4:2.

The direction of the measurement matters. Draw the line:

Iron Nest → Target

For my Calibration Fire order, that produced approximately 85.4° bearing and 8.90 km range.

Drawing the line in the opposite direction can give you a completely different bearing.

2. Build the Ballistic Solution

At the ballistic calculator, enter the information from the map.

For this shot:

• Range: 8.90 km
• Bearing: 85.4°
• Shell: HE
• Powder charges: 2

The firing solution used in the video gives the left gun an elevation of 53.40°.

3. Load the Left Gun

Select the HE shell and complete the shell-loading process.

Then load exactly two powder charges.

This is an important troubleshooting point. Calculating the shot for two charges does no good if the physical gun is loaded with a different number.

4. Set Bearing and Elevation

Rotate the turret toward 85.4°.

Use the larger control for major movement and the fine control when you are close to the desired bearing.

Next, set the left gun to 53.40° elevation.

If the elevation controls appear locked, allow the loading process to finish completely before trying to move the gun.

5. Complete the Firing Check

At the firing station:

• Confirm the firing mission
• Confirm the shell
• Confirm bearing
• Confirm elevation
• Arm the left gun

Then fire.

Strategy Takeaway

Treat Calibration Fire as a checklist rather than one big puzzle:

Orders → Map → Ballistics → Load → Bearing → Elevation → Readiness → Fire

When a shot fails, go back to the stage most likely responsible instead of changing everything at once.

A huge miss usually points toward bearing, range, charges, or elevation. A gun that won't operate usually means part of the loading or readiness sequence is incomplete.

Related IRON NEST Guides

• Next tutorial: Coming Soon
• IRON NEST Tutorial Hub: Playlist

Which part should I cover in more detail next: map plotting or the ballistic calculator?