Significance of the 3rd groove?

Whats the significance of 3rd groove on the irons? When you remove the offset, why line up with the 3rd groove down the shaft?

I thought this was a little peculiar. After hitting my 6, 7, and 8 irons. I found the line of dirt or wear going across the 3rd groove. Below is a picture of my irons after 2 hour practice. Granted these are not the best or the most impressive impact marks lol…but im working on it. :wink:

I was hitting my 7 iron pretty decent. My best shots would just check right on the spot after it landed. Surprised i could put that much spin on range balls…


Shallow entry with a bacon strip divot will contact the ball about on the third groove for the longer irons… and up to about the 4rth groove with the shorter irons due to the loft of the club compressing the vertical disposition of the grooves… therefore it is suggested here that you have the impact point of your clubs into the same relative area on the club in relation to the shaft. This way you don’t have to make any compensations in your swing regarding how you release the club.
The short irons should have just a slight bit of leading edge face progression because the loft of the club pushes the grooves back and down.

Thanks Lag! I have notice that blades cut into the turf a lot cleaner and take a nice even strip when hit correctly. I have also noticed that all my divots lift up out to my left side. Do the classic irons have more loft then todays irons? I feel that my Hogan’s are about one club weaker then my modern iron’s in distance.


Generally speaking, about a club shorter seems to be a good rule of thumb, based on weaker lofts (more loft) and shorter shafts. All of my older sets are roughly a club shorter than my Mizuno MP68’s.

Thanks JRich! Glad im not the only one who felt that haha…

I have wondered about this - when you take the head off the shaft and you try to balance the face of the clubhead onto a ballpoint pen (I presume that this represents the COG in the face of the plane)…it is alot higher than the third groove in my experience (Hogan power thrust 1960,1962) …somewhere between 5th and 7th grooves…

COmpare with the Yonex Driver advert which do something similar:

Can someone explain?? Isn’t the COG of the clubhead the sweetspot? Does it change when shaft is in the club?


Some thoughts on offset and how it differs from face progression: … asics.html … ffset.html … techKey=26

Helps a bit…

Again, there are differences between hitting and swinging and how clubs should be ideally set up.

Wishon is correct in that offset allows more time for the club to square up… but this is a swinger’s protocol.
A hitter is actively rotating the forearms, and you want to be rewarded for your efforts… not forced to over rotate which usually promotes OTT also.

When the back of my left hand (for reference) squares up at impact, I want the clubface squared up also… I don’t want to wait for the face to square up because it is offset… or have to rotate the forearms more than I need to… or come OTT to do it.

As far as the COG on the club… the ball will make initial contact ideally about the third groove for better strikers… but as the clubhead continues to slightly descend after initial contact, the ball is compressing into the face of the club therefore some of the mass is moving up the clubface.

After practicing with zero offset for a while, then switching back over to an offset club, would a person naturally hit the ball a little fat at first until they adjust for the offset delay?