Butt-end mass: what a counterweight actually moves

Filed from the vice · Bay View, Milwaukee

A counterweight is a lump of mass installed inside the butt end of the shaft, usually under the grip cap, typically somewhere between ten and fifty grams. There is nothing mysterious about it. It is mass placed close to your hands rather than out at the head.

What it does, precisely

Two things happen simultaneously, and people usually only get told about one of them.

First, total mass goes up. If you install a twenty gram counterweight, the club now weighs twenty grams more than it did. That is not a feel effect, it is arithmetic, and it will affect your tempo the way any total mass change does.

Second, swing balance goes down, by roughly five points for twenty grams at the butt. The head feels lighter, because you have shifted the balance of the assembly towards your hands. This is the effect that gets marketed, and it is real.

You have made the club heavier and made the head feel lighter, at the same time. Whether that combination helps you depends entirely on which of those two things was your problem.

The two honest use cases

Case one: a club that is too long and cannot be cut. Occasionally somebody arrives with a driver that is too long for them but which they will not shorten, usually because it is a shaft they love and cutting is irreversible. Counterweighting brings the balance back under control without touching the length. It is a compromise and I will say so out loud, but it is a genuine one.

Case two: a golfer who wants more total mass without more head feel. This shows up with players who are fighting a quick transition. More mass smooths the change of direction, but adding it at the head makes the club feel unwieldy. Adding it at the butt raises the total while keeping head feel where they like it. That is a legitimate and quite specific fix.

The dishonest versions

The claim that counterweighting increases club head speed is where I get impatient. The argument usually goes that a lighter feeling head lets you swing faster. Sometimes a golfer does swing marginally faster with a lower swing balance. They are also swinging a heavier club overall, which pushes the other way, and in every set of measurements I have taken on this bench the two effects roughly cancel out for most people.

What I have seen consistently is a change in where on the face the ball gets struck, which is a different and often more valuable benefit. If reducing head feel tightens a golfer's strike pattern, they will gain distance. That gain came from centre contact, not from speed, and describing it as a speed gain is how a useful adjustment becomes an oversold one.

The other dishonest version is counterweighting an entire set to hide a build problem. If a set has inconsistent head masses, the correct fix is at the head. Papering over it with butt weights makes every club heavier and does not actually restore progression, it just moves the inconsistency to a different number. We will not do it, and we will explain why if somebody asks us to.

How we test it before committing

Counterweighting is reversible while a grip is off and inconvenient afterwards, so we test with temporary mass first. Weights go in, you hit fifteen balls, weights come out, you hit fifteen more, and we look at the strike map rather than the distance figure. That is a twenty minute exercise at the end of a driver bench session and it costs nothing extra.

About one golfer in five who asks about counterweighting turns out to benefit from it. That is not a low number for an adjustment this cheap, and it is a long way from the universal upgrade it is sometimes presented as.

If it helps, we record it

Field 09 on the sheet is installed tip weight and field 10 is installed butt weight, both in grams, both measured rather than assumed. A counterweight is invisible once the grip is on. Without a record, the next person to work on that club has no way of knowing it is there, and a re-shaft five years later will produce a club that inexplicably feels wrong.

Which is, ultimately, the recurring theme of everything in this log. The adjustment is rarely the hard part. Knowing what was done, three years after the person who did it has forgotten, is the hard part.

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