Ballistic Calculator Guide — Iron Nest Wiki

Launch Version / Updated: August 11, 2026

The ballistic calculator is the machine that turns map measurements into gun settings. You give it five inputs; it gives you a firing card with the rotation and elevation for the shot. You never compute a trajectory yourself — the machine does it. Your job is to feed it correct data, in the correct order.

This guide covers the basic five-input firing solution first, then what the calculator does NOT account for: wind and weather, the correction workflow for "short" and "over" reports, and how to shoot reliably at the very edge of the gun's range. Correction figures are community-reported — the game does not publish its full ballistics table, so treat them as starting points verified by operators, not official numbers.

The Five Inputs

1. Distance to Target

Rotate the wheel until the counter matches the range from your clipboard exactly. This is the range measured from the Iron Nest's own position — not from the spotter. If your clipboard holds the spotter-to-target range, draw the Iron Nest-to-target line on the map first (red pencil) and use that value.

2. Bearing to Target

Enter the bearing with the large (coarse) and small (fine) wheels. Match the value on your clipboard digit for digit. A one-degree error at 5 km is roughly a 90-meter miss — double-check.

3. Shell Type

Select the ammunition you intend to fire. High Command sometimes dictates the ordnance for a mission; otherwise pick from your requisition stock. Heavier shells arc higher and drop more — the calculator accounts for this, so never "help" it by adjusting elevation manually.

4. Powder Charges

Select the number of charges required for the target's distance using the chart on the machine. Fewer charges = shorter, lower-arcing shot; more charges = longer range. The charge count must match exactly what you load into the gun — the calculator assumes the charge count you enter.

5. Target Classification

Choose the target type: Infantry, Recon, Artillery, Mechanized, Fire Director, or Supply Cache. The classification can affect the recommended shell and helps the calculator refine the solution for the target's size and hardness.

Generating the Firing Card

Pull the lever to calculate. The machine prints a firing card with two values:

Gun elevation — shown lower-left (the angle to set on the elevation console)
Gun rotation — shown upper-right (the bearing to set on the rotation controls)

The card attaches to your clipboard automatically. Take both values to the gun stations — do not eyeball them from across the room.

The Shot Cycle

Rotation first. Rotating 360° takes time — start the rotation before you fine-tune elevation.
Elevation after loading. The elevation console stays locked until the gun is loaded, and resets to zero after every shot.
Fire, observe, correct. Watch the radio report: a red skull means the kill; a report of "short" or "over" tells you how to correct the next shot. Shells can take a long time in flight at extreme range — never fire a correction before the previous round has landed.

Corrections — MOA and the Short/Over Workflow

Mid-game corrections arrive in Minute of Angle (MOA) terms, and the game's dials use click-steps. MOA is an angular unit that scales with range: a correction that moves the impact a little at close range moves it much more at long range. That is why you should always correct in clicks/MOA, never in meters — the same click count does the same angular job at every distance.

From Phase 2 onward, spotters radio impact corrections: "Impact 100 meters short, 50 meters left." The fastest path back on target is not a new firing card:

Convert the report to dial terms. The short/over distance at your current range converts to a dial correction — do not recalculate from scratch.
Apply it to the live dials — elevation for short/over, rotation for left/right. The arrow keys at the elevation console are the precision correction tool; use them instead of the coarse lever.
Wait for the round to land before correcting again. A "correction" fired before the previous round lands is a shot at a ghost.
Confirm with a second source — a second spotter or a star shell — before treating the corrected shot as the kill.

Community practice notes on dial corrections (approximate, not official):

Situation	Community Practice
Heavy shells at long range	Drop more than light shells — dial up extra elevation beyond the card
Dense fog	Add elevation — fog pushes impacts short
Strong crosswinds	Hold rotation into the wind, and expect elevation loss on light rounds

Wind & Weather — The Weather Station Module

From Chapter 3, the Weather Station Module forces environmental ballistics on every long shot. Two effects matter:

Crosswind

Pushes the shell sideways. The strength of the effect depends on the shell:

Heavy projectiles (HE, AP) cut through wind but drop more aggressively — expect to add elevation.
Light rounds (S.T.A.R. illumination) get blown significantly off target if you ignore wind — a star shell at extreme range in a gale may illuminate nothing at all.

Community practice: in steady crosswind, hold rotation into the wind before fine-tuning with the wheel. Treat the weather readout as part of the firing solution, not decoration.

Barometric Pressure

Low barometric pressure means thinner air — less drag, so shells fly farther and flatter than the calculator predicts. Community-reported: with a low-pressure system over the map, reduce elevation slightly below the card's value or the shell overflies. High pressure does the opposite — add a touch of elevation. The effect grows with range.

Night, Fog & Limited Visibility

Fog is an elevation problem: dense fog pushes impacts short, so add elevation (community-reported).
Night is a visibility problem: fire a S.T.A.R. illumination shell first — it reveals positions across a huge area and does not start counter-battery fire (see the reconnaissance guide). Time it so the reveal and the kill shell overlap.
In both conditions, treat spotter reports as looser — the error budget below applies.

Spotter Reliability at Range

Spotter reports carry error that grows with distance (community-measured):

Short range — spotters are effectively authoritative; trust the report.
Mid range — declining; treat reports as good estimates.
Beyond extreme range — treat reports as advisory only.

Past the mid-range band, prefer triangulation from multiple observers, or a star-shell reveal, over any single report — and expect to do the short/over correction dance on the first round.

Recon Flights and Your Firing Corridor

A recon flight is not a scouting tour — it is a ballistics input. Recon planes fill in map blanks and reveal terrain, and that terrain is what tells you whether a shell will clear a ridge on its way to the target.

Fly the corridor you intend to shoot. Send the recon plane along the line between the Iron Nest and the target area (community practice for the gorge missions is roughly 90° east along the firing lane). Broad, unrelated photography looks productive and answers nothing.
Use the terrain to adjust elevation. Ridges between you and the target are the main reason a card-perfect solution still hits short — the imagery shows you what the shell has to arc over, so you know where to add elevation.
Recon the corridor before long shots, not after. At extreme range a flight costs less than a wasted heavy shell and its reload.
Recon is intel, not a firing solution. The plane does not give you range and bearing — spotters and star shells do that. It tells you what the ground between you and the target looks like.

If the flight reveals a ridge you cannot arc over at your current charge count, that is a signal to reposition or pick a different firing lane rather than to trust the calculator's elevation. See the reconnaissance guide for the other intelligence assets.

Extreme-Range Shooting (10–20 km)

At the far edge of the envelope everything gets worse at once: longer flight time, larger drop, more wind exposure, and less reliable spotter data. The extreme-range playbook:

Verify with illumination or recon imagery first — never burn a long flight on a guess.
Dial the heavy-shell drop corrections rather than trusting the basic card alone.
Fire one ranging shot, wait for its full flight time, correct from the impact — the ranging-shot correction works at any range.
Mind the barrel — extreme-range firing is usually slow fire anyway, which suits the heat ceiling (see systems & failures).

The Long-Shot Checklist

[ ] Weather station read — crosswind? pressure? fog?
[ ] Shell flight time estimated — corrections fired only after the previous round lands
[ ] Multi-observer confirmation for anything beyond extreme range
[ ] Heavy-shell drop correction dialed in addition to the card
[ ] Windage held into the wind for light rounds
[ ] One ranging shot, one correction, one kill

Common Calculator Mistakes

Mistake	Result
Entering spotter-to-target range instead of Iron Nest-to-target range	Systematic overshoot or undershoot
Wrong powder charge count vs. what is loaded	Shell falls short or overflies — and you cannot unload it
Misreading the bearing (180° off)	A clean miss into friendly territory
Setting elevation while the calculator card is stale	Firing an old solution at a new target

The 30-Second Rule

Before you pull the lever, run the check: clipboard range matches the map, bearing matches the target token, shell type matches the load, charges match the chart, classification matches the orders. Thirty seconds of verification saves five minutes of reloading. For the mechanical side of the shot, see the loading & aiming guide.