🎯 FireMission

Hell Let Loose: Vietnam — Mortar Guide

Last reviewed August 17, 2026. Mechanics below are the parts common to all Hell Let Loose indirect fire; Vietnam-specific numbers are marked as unverified until the community table is confirmed.

Degrees vs mils — Vietnam changed the dial

Classic HLL artillery aims in milliradians("mils", 6400 to a circle): US guns drop from 978 mils at 100 m to 622 mils at 1600 m. Vietnam mortars instead aim by barrel angle in degrees, from 85° (100 m, near vertical) down to 0° (450 m, max throw). Same physics either way: steeper barrel, shorter throw — which is why every table runs downward as range grows.

The three-step firing loop

  1. Range the target. Use the map grid: one large grid square is a known width, so count squares between your gun and the target mark. Your spotter's ping distance is the cleaner source when available.
  2. Convert to a barrel setting. That is what the calculator does — verified angle chart with interpolation between rows (100–450 m, 85°–0°).
  3. Walk corrections. Watch the impact (or have your spotter call it): short → flatten the barrel a couple of degrees, long → steepen it. Inside 300 m figure roughly 6° per 25 m; past 300 m the curve flattens. Persistent disagreement with the chart is worth reporting — it is how the table gets hardened or split per faction.

Building the Vietnam range card (community effort)

Because Vietnam's tables are unpublished, the honest path is the one the original HLL community walked years ago: pick a landmark at a known distance, fire until you hit it, record the mil, repeat at a second distance. Two clean readings define the line; a third confirms linearity. The calibration page explains the cleanest measurement procedure and how to submit readings for the verified preset.

Squad etiquette that gets you readings faster