Projectile speed in Rust: why lead depends on the weapon, the ammunition and the range
There is no single "bullet speed" in Rust. There is a table: a set of values per weapon, and within one weapon the speed changes in steps by range. An ammunition multiplier scales it on top. Here is how that turns into the point you have to aim at.
Speed is not a constant
The first thing that breaks intuition: projectile speed in Rust is neither constant nor smoothly decaying. It is set in steps.
For the AK-47 that is 386 m/s out to 150 metres, 390 to 200, 400 to 250 and 410 to 300. The Thompson runs the other way — 270 m/s to 180 metres, then 250, 245 and 230. The Bolt Action Rifle sits flat at 579 m/s and the L96 at 1126, twice as fast.
The steps are not invented: they are measurements from the game collected into a table. Replacing them with a single formula means missing at every interval boundary.
The ammunition multiplier
On top of the weapon's speed sits the ammunition coefficient, and it is a strong one:
| Ammunition | Multiplier |
|---|---|
| Standard (rifle, pistol, handmade) | 1.0 |
| HV (high velocity) | 1.2 rifle, 1.33 pistol |
| Incendiary | 0.55 rifle, 0.75 pistol |
| Explosive | 0.49 |
| Buckshot / slug | 2.25 |
| Arrows: wooden / HV / fire | 1.0 / 1.6 / 0.8 |
A factor of more than two between HV and explosive means a different flight time and a different lead from the same weapon. Changing ammunition shifts your aim as much as changing guns.
What the aim point is made of
t = range / speed(weapon, ammunition, range)
point = target position + v_target · t · 0.75 + 4.905 · t²
The third term is simply ½·g·t² at g = 9.81 m/s²: how far the round falls during the flight.
The second term is the lead, and the 0.75 in it is not arbitrary. The target's full velocity would be right if the target held it for the entire flight. In Rust it almost never does: players accelerate, brake, change direction, catch on terrain. The reduced coefficient pulls the meeting point closer to the target and lands more hits in practice than the mathematically "correct" full correction.
What it means in a fight
Three consequences that are useful with no software at all:
- A bow and a bolt-action are different universes. 55 m/s against 579: at 150 metres the flight time differs tenfold, and so does the lead.
- The step works against you at a boundary. Between 180 and 204 metres the Thompson drops from 270 to 250 m/s — almost a tenth, for nothing.
- Ammunition changes your aim. Switch from standard to explosive and the lead doubles, at the same range with the same gun.
What the calculation is used for and how it is configured is in the Rust cheat description. Other games take a different route: PUBG decelerates the bullet with a physical model and accounts for sight zeroing, while War Thunder integrates the trajectory numerically.
If the product will not start, the step-by-step breakdown is in the launch guide.