How TTK works in Delta Force
Time-to-kill looks like a simple division — until armor gets involved. Here is the full chain: fire rate to bullet interval, damage to shots-to-kill, and the tier-gap model that decides how much of your damage a plate actually eats.
Quick answer
TTK = (shots to kill − 1) × 60,000 ÷ fire rate in RPM. Shots to kill is your target's health divided by the damage each shot deals after armor — and against armor, "damage after armor" depends on your ammo tier versus the target's armor tier, not just the number on the gun.
Step 1 — fire rate to bullet interval
A gun firing 700 RPM puts a bullet in the air every 85.7 milliseconds:
interval (ms) = 60,000 ÷ RPM
The first shot is free — it happens the instant you press the button — which is why the formula subtracts one interval.
Step 2 — damage to shots-to-kill
shots = ceil(health ÷ damage per shot)
Unarmored, that's the whole story: a 42-damage gun needs 3 shots on a 100-health operator. Armored, the damage per shot collapses:
damage per shot = dmg × (pen + (1 − pen) × blockedShare)
Where pen is the penetration chance from the ammo-vs-armor tier gap, and blockedShare is the slice of a blocked shot that still hurts (community estimate ≈ 30%). Same 42-damage gun with same-tier ammo: about 29 damage per shot reaches health — 4 shots instead of 3, and that assumes a fresh plate.
Step 3 — the plate is a second health bar
Blocked damage chips armor durability. A 50-point plate dies to a stream of blocked shots, and after it breaks, every bullet lands at full damage. That's why TTK against armor is a two-phase problem, and why a "half-dead" plate changes fights: the calculator reports the exact shot on which armor breaks.
Worked example
| Scenario | Shots | TTK @ 700 RPM |
|---|---|---|
| 42 dmg, no armor | 3 | 171 ms |
| 42 dmg vs same-tier armor, 50 durability | 4–5 | 257–343 ms |
| 42 dmg, ammo 2 tiers under | 6+ | 429+ ms |
Illustrative values from the tier-gap model — reproduce them with your own inputs on the TTK calculator.
What TTK doesn't tell you
- First-shot reliability — a 171 ms TTK means nothing if the first two shots miss.
- Range — falloff lowers damage; enter a reduced "damage at range" percentage in the calculator.
- Aim trajectory — headshot multipliers end fights faster than any RPM number; multipliers are input-controlled in the tool because they vary by helmet and ammo.
Sources and verification
The tier-gap model and its rebalance history are community-documented; our standing assumptions, with sources and the [VERIFY] policy, live on the methodology page. Game patches change these values — always check the review date before quoting numbers in an argument.