Put two 7-irons on the machine, both stamped 31 degrees, from different manufacturers. Both may genuinely measure 31. They will still not carry the same distance for the same golfer, and the difference is often eight to twelve yards.
Reason One: Length
A 7-iron is not a standard length. Across the sets that come through this room the spread runs close to three quarters of an inch between the shortest and the longest, which is worth a few yards on its own and also changes strike quality. A manufacturer chasing a distance number can add loft strength and length together, and often does.
Reason Two: Head Design
Where the mass sits in the head changes where the centre of gravity sits, which changes launch and spin for the same delivered loft. A wide-soled cavity with a low centre of gravity launches higher and spins less than a compact blade at identical loft, and those two effects push carry in opposite directions by different amounts.
This is why comparing lofts across brands is close to meaningless. The stamped number is one input into a system with several others.
Reason Three: Delivery
The biggest factor is you. Dynamic loft, meaning what the face actually presents at impact, can sit several degrees either side of the static number depending on shaft lean, attack angle and where on the face contact occurs. Two golfers with the same club can deliver loft five degrees apart, and that is a bigger effect than any equipment difference on this page.
Then It Drifts
Everything above is true on day one. From day one it gets worse, because forged and cast heads alike bend a little in normal use. Turf contact, mat practice and the occasional root all move a hosel by a fraction of a degree, and it accumulates unevenly across a set because you do not hit every club equally often.
The pattern in our records is consistent: after three seasons of regular play, a set that left the factory matched typically shows a spread of one to two degrees across the middle irons, with the worst drift in the clubs used most. Wedges drift fastest of all.
| Club | Typical drift | Carry effect |
|---|---|---|
| Long irons | Under 0.5° | 1 to 2 yd |
| Mid irons | 0.5° to 1.5° | 2 to 5 yd |
| Short irons | 1° to 2° | 3 to 6 yd |
| Wedges | 1° to 2.5° | 3 to 8 yd |
Why This Matters More Than It Sounds
Nobody notices a two yard change on one club. What people notice is that the ladder has gone uneven: the 8-iron and the 9-iron now sit six yards apart while the 7 and the 8 sit fourteen apart. Confidence in the whole middle of the bag quietly erodes, and the golfer usually blames their swing.
The Fix Is Cheap
Bending a set back to a proper ladder is bench work, not a purchase. A recheck every spring catches drift before it becomes a spacing problem, and it costs less than a round of golf. If a head has been bent repeatedly or is a casting near its limit, we will tell you before it goes in the machine rather than after it cracks.