CS2 Damage Explained: Why the M4A4 Can Never One-Tap

You hit the headshot. You saw the blood. The enemy turned around and killed you.

You check the kill feed, you do not believe it, so you open the demo and watch it again. The crosshair was on the head. The bullet went into the head. He lived anyway.

That was not desync. That was not subtick. If you were holding an M4A4 and he was wearing a helmet, that bullet was never going to kill him. Not at any distance. Not even pressed against him.

And you can prove it with one multiplication.

The formula behind every duel in CS2

Everything that happens when a bullet lands runs through the same equation:

damage = base damage x hitbox multiplier x armour penetration x range modifier ^ (distance / 500)

Four numbers. That is the whole system.

Base damage is what the gun does to an unarmoured chest at point blank. The AK-47 has 36. The M4A4 has 33. The AWP has 115.

The hitbox multiplier rescales that number depending on where the bullet lands. The head is x4.00. The stomach and pelvis are x1.25. The chest and arms are x1.00. The legs are x0.75.

Armour penetration is the share of damage that survives contact with armour. The AK-47 keeps 77.5%. The M4A4 keeps only 70%. That gap is the entire story of this article.

The range modifier is how much damage the bullet sheds over distance. The AK-47 sits at 0.98, meaning it loses 2% of its damage for every 500 units travelled. One metre in CS2 is roughly 39.4 units, so 500 units is about 12.7 metres.

One thing to lock in before we go further: kevlar covers the chest, the arms and the stomach. The helmet covers the head only. Legs are never protected by anything.

Why the M4A4 cannot one-tap through a helmet

Run the AK-47 headshot against a helmeted enemy at point blank, so there is no range loss at all. That is 36 base damage, times the 4.00 head multiplier, times 0.775 armour penetration, which comes out to 111.6.

111.6 damage against 100 HP. Dead.

Now run the exact same calculation for the M4A4. That is 33 times 4.00 times 0.70, which comes out to 92.4.

92.4 damage against 100 HP. Alive, with 7.6 HP left.

And 92.4 is the M4A4's best possible result, at zero metres. The range modifier only ever subtracts from that number, it never adds. So if the ceiling is 92.4 and the ceiling sits below 100, the M4A4 cannot kill a helmeted enemy with a single shot to the head. Not at any range in the game.

It is not a bug. It is not the server. The gun was designed this way.

That chart should change a few of your buy round habits.

The M4A1-S one-taps through a helmet. The M4A4 does not. Both rifles share the same 70% armour penetration, but the M4A1-S has 38 base damage instead of 33, which lands it on 106.4. It clears the line. That is the single most important difference between the two guns, and nobody mentions it while arguing about recoil and magazine size. If you want to see what the people who do this for a living actually run, the full table is in our CS2 Pro Settings 2026 guide.

The SG 553 has 100% armour penetration. A helmet does nothing against it. Thirty base damage times four is 120, with nothing taken off. It is the only gun in the game that ignores armour completely.

The Tec-9 and the Five-SeveN clear the one-tap threshold more comfortably than the AK-47 does. Tec-9 lands at 119.6, Five-SeveN at 116.6, AK-47 at 111.6. Two force buy pistols beat the AK on this specific metric, because both sit above 90% armour penetration.

The AUG clears the line by 0.8 damage. It lands on exactly 100.8. Technically a one-tap, but the margin is so thin that falloff eats it within the first few metres. Past that point, the AUG behaves exactly like an M4A4.

The P250 misses by 2.7. 97.3. That close, and still never.

The Negev and the M249 one-tap through a helmet. Yes, really. Two LMGs nobody buys do something the M4A4 cannot.

The stomach beats the chest, on every single gun

Everyone says aim for the chest. Everyone is wrong.

The stomach carries a x1.25 multiplier. The chest carries x1.00. Both are covered by kevlar, so armour penetration applies identically to each. The result is simple: the stomach takes exactly 25% more damage than the chest, for every weapon in the game.

With an AK-47, against an enemy wearing kevlar: chest is 27.9 damage, so you need 4 bullets. Stomach is 34.9 damage, so you need 3 bullets.

One bullet of difference. On an AK spray, one bullet is roughly 100 milliseconds. In those same 100 milliseconds, your opponent finishes his own spray.

Look at the middle column. On almost every gun in that table, the stomach saves a full bullet over the chest. The SG 553 kills in 3 stomach shots. So does the AK-47.

In practice this means one thing: when you spray transfer, or when you are holding an angle for someone to peek it, do not drop your crosshair to chest height. Keep it at stomach height and let recoil walk the gun up through the chest and into the head. The early bullets land where they hurt most.

Two things make that easier. First, a crosshair you can actually see against a wall, which you can build in our CS2 Crosshair Generator. Second, stopping properly before you shoot, because a moving first bullet lands nowhere near where you placed it. We cover that in the CS2 movement guide.

Legs are the one place kevlar never reaches

This is the part almost nobody uses.

Legs carry a x0.75 multiplier, which makes them look like the worst hitbox on the body. But legs are never covered by kevlar. Armour penetration does not apply there at all.

That means for guns with low armour penetration, legs do more damage than the chest does.

The Glock-18 has 47% armour penetration, the lowest in the game. Through kevlar, its chest shot deals 14.1 damage, which is 8 bullets to kill. Its leg shot deals 22.5 damage, which is 5 bullets to kill.

Eight bullets versus five. On pistol round with a Glock, shooting someone's legs kills them three bullets sooner than shooting their chest.

The USP-S tells the same story: 6 to the chest, 4 to the legs. The UMP-45: 5 to the chest, 4 to the legs.

One thing needs saying plainly, so this does not get misread: this is not a rifle round strategy. With an AK-47, legs deal 27.0 and an armoured chest deals 27.9, which is effectively identical, and the head remains by far the best target. The leg trick matters on eco rounds, pistol rounds and force buys, exactly the rounds where every bullet counts and where the enemy has armour that you do not have the gun to punch through.

It is also worth knowing that stretched resolutions change how wide those hitboxes look on your screen without changing the maths behind them at all. We measured exactly what you gain and lose in 4:3 Stretched in CS2.

The AK-47 loses its one-tap at 69 metres

The range modifier is not a rounding detail. For the AK-47 it is 0.98, which means the 111.6 damage it starts with gets multiplied by 0.98 for every 500 units the bullet travels.

At zero metres it returns 111.6. The margin above 100 HP is 11.6 damage. Falloff chews through that margin slowly, but it does chew through it.

The AK-47 drops to exactly 100 damage at 2,716 units, which is roughly 69 metres.

69 metres is further than it sounds. For reference, the long sightline on Dust2, from T spawn toward long doors, does not reach it. In practice, across the Premier map pool, the AK-47 one-taps through a helmet in essentially every spot where you have a realistic chance of hitting a head in the first place.

The grey dotted line on that chart is the M4A4's ceiling. It never crosses the 100 HP line, because it starts below it.

What to change in your next match

Four concrete things, in order of how much they matter.

1. If you play CT and you want the one-tap, take the M4A1-S. Not for the silencer, not for the recoil. Because 106.4 clears 100 and 92.4 does not. If you prefer the M4A4 for the 30 round magazine and the higher rate of fire, that is a defensible choice, but accept that you have no helmeted one-tap and play for two bullets instead.

2. Hold your crosshair at stomach height, not chest height. At the right height, the first bullet that misses the head lands in the stomach rather than the chest, and that is 25% more damage on every shot that does not quite get there.

3. On pistol round with a Glock, shoot the legs. Five bullets instead of eight against an armoured enemy. Given the Glock's spread, the legs are also a bigger and more forgiving target than the head.

4. If you want a gun that ignores helmets entirely, buy the SG 553. 100% armour penetration. It is the only one.

None of this matters if your crosshair is not on the head in the first place, and that is a sensitivity problem far more often than an aim problem. If you came from another shooter, convert your number properly with the CS2 Sensitivity Converter, and check what your current setting actually works out to with the eDPI Calculator.

And if you keep losing the same duels round after round even when you know all of this, the problem is further upstream. Start with Why You Are Not Improving at CS2.

Next time you hit a headshot and the enemy does not die, open the console, check which gun you were holding, and do the multiplication. In most cases, the number will tell you the game worked exactly as designed.