Iron Nest Mission 4: Counter-Battery - CBT Solutions

Worked example: Bearing, range, charge and elevation figures below come from a sample playthrough. Enemy spawns and your Iron Nest’s position vary each run — always measure on the map and follow the in-game ballistic calculator.

Mission Critical Strategy: The CBT Rule

Counter-Battery is widely considered the first major skill check in Iron Nest. Everything up to this point has been generous with time: you measured, you calculated, you fired. Mission 4 flips the order. Here, firing is what starts the clock, and the clock is what kills you.

The enemy operates acoustic radar that detects your gun’s muzzle blast the instant it happens. That detection arms a strict 120-second Counter-Battery Timer (CBT). When the timer expires, an overwhelming artillery barrage obliterates Iron Nest. There is no partial survival state and no way to shoot your way out of it — the only defence is to have already finished the fight before the number reaches zero.

The doctrine that solves the mission is therefore counter-intuitive: spend the entire pre-engagement phase not firing. Every bearing and elevation you will need is measured, written down and physically loaded into the guns before the first lanyard pull. Once the clock starts, you are no longer solving a problem — you are executing a checklist you built in advance.

The flight window is not dead time — it is your traverse time

The single biggest mistake new operators make under the CBT is standing at the observation window to watch the first shell land. A shell fired at 10.13 km takes roughly 14 seconds to arrive. Fourteen seconds is more than enough to swing the turret from 085.2° to 092.4° and select the other gun — and it is exactly the time you cannot afford to spend watching.

Reframe the shot: the lanyard pull is not the end of an action, it is the start of a fourteen-second window in which the turret should already be moving to its next target. If you are still looking downrange when the impact lands, you have converted your slack time into nothing.

[!WARNING] The CBT is armed by your muzzle blast, not by the enemy’s. There is no way to fire a ranging shot without starting the clock, and no way to stop the clock once it runs. Any plan that involves “fire and see what happens” is a plan to fail — everything must be resolved on the map first.

Reading the reinforcement interrupt

Phase 3 exists because the mission does not let you simply fire twice and leave. At roughly 80 seconds remaining, the teleprinter prints a new contact — a reinforcement battery in Sector D7. It is a short, flat shot at 11.50 km and it demands APHE rather than H, but the important detail is that it arrives while you are already inside the window. If you entered the timer with only two solutions prepared and no room in the schedule, this interrupt is what breaks you. If you entered with a clean two-shot opening, you still have roughly 60 seconds of slack left when the third target appears — enough to load, traverse and fire with time to spare.

Pre-Calculated Firing Solutions

Do not spend time calculating while the timer ticks down. Use these verified operational values:

The ammunition budget follows directly from this table: three targets, one round each, three charges per round — 2 H shells, 1 APHE shell, 9 charge bags. Draw all of it in Phase 1. Returning to the locker mid-timer is a loss.

Step-by-Step Operator Routine

Phase 1: Pre-Engagement Preparation (Timer: Stopped)

1. Read the teleprinter dispatch and confirm the three hostile locations on your map.
2. Measure all three target lines now, with the ruler anchored on the bottom spike of the Iron Nest icon, and write the six values down.
3. Go to the ammunition locker: retrieve 2 H shells and 1 APHE shell, plus 9 powder charge bags.
4. Load Left Gun: 1 H shell + 3 charge bags. Set elevation to 40.52°.
5. Load Right Gun: 1 H shell + 3 charge bags. Set elevation to 56.80°.
6. Rotate turret traverse to 085.2° (aligned for Left Gun).
7. Re-read every value once before you touch the lanyard. This is the last moment at which an error is free.

Phase 2: Opening Salvo (Timer: 120s → 100s)

1. Select LEFT GUN on the selector console.
2. Pull the firing lanyard. (CBT timer begins immediately).
3. Confirm hit on Battery Alpha.
4. Immediately traverse turret +7.2° right to 092.4°.
5. Select RIGHT GUN and pull the lanyard.
6. Confirm Battery Bravo neutralized. (CBT Time Remaining: ~90s).

Phase 3: Reinforcement Battery Neutralization (Timer: 90s → 60s)

1. At 80s remaining, the teleprinter prints: Reinforcement battery detected in Sector D7.
2. Traverse turret to 078.0°.
3. Load Left Gun with 1 APHE shell + 3 charge bags.
4. Adjust inclinometer to 46.00°.
5. Pull lanyard. Confirm direct penetration.
6. High command confirms: Primary objective complete. Stand down authorized.
7. Do not relax until the stand-down order is printed. Keep the turret where it is and watch the timer bleed out with the mission already completed.

[!IMPORTANT] Operator Rule: Do not stand at the observation window to watch the first impact. The flight duration is approximately 14 seconds. Use that flight window to traverse the turret toward Battery Bravo.