24/38 Rule

I have heard of it. It was a rule of thumb among old school clubmakers that average golfers would never be able to consistently hit any iron with a loft of less than 24 degrees or a length of over 38 inches. Tom Wishon (a well-respected modern club designer) estimates that 90% of golfers do not have either the swing speed or skill to hit an iron with < 24 degrees of loft properly even half the time.

Kind of sad because on some modern iron sets, the (alleged) "5 iron" is now 22 or 23 degrees and 38.25 to 38.5 inches. Silliness.  

Yup, 24°/38" is my 5 iron exactly. I think that it is important to remember though what clubs were like in the 70s and 80s... they were a lot less forgiving and all of that so a club that is 24/38 now isn't as hard to hit as a club from then with those specs.

I took a look in the Maltby Golf Club Design / 4th ed book (p. 844) to get iron specs from 1970s. Titleist specs from 2010 product catalog, TaylorMade specs from current web site (note: TM no longer lists club specs in its 2013 product catalog). 

*Acushnet is the parent company for current-day Titleist and Footjoy products.

One interesting point on the ever-stronger lofts: Ping originally strengthened its innovative perimeter-weighted irons 2° to prevent slight distance loss. Perimeter weighting got ball up better and higher, but at a cost of a few yards of distance compared to comparable irons of the day.  So, 2° is understandable, but then the marketing guys went wild and we have ended up with the battle for the 200-yard 7 iron (courtesy of TM).

Needless to say, clubhead design advances from then to now should be considered in your loft comparisons.

As for greater shaft length, GolfWorks reminds us that people are growing taller than in the previous generations, so that partly explains the longer shafts.

My MP-57 4 iron is 24 and 38.25".  I hit it ok about 50% of the time, but not as reliable as the 5 iron.  I use the 3-iron for practice though and not on the course.

My longest iron is a 39" 3 iron at 21 degrees. I was crushing it off the deck last time I hit some balls. I also have an old blade 1 iron that I hit off the deck a couple times; about 39.25" and 17 degrees. Though it wasn't very forgiving obviously (toe hits lost 40 yards vs the 3i) and the shaft is bad for me, I could get it in the air OK. It was less accurate than the 3i based on my few shots, but it went a lot farther. Carry was about the same but the 1i had a very shallow descent and lower peak, I'd say 10-20 feet lower. This is with a handful of range balls apiece of varied condition, hitting a standard fade. The shaft on the 1 iron was lighter and softer, though I don't think it made much difference outside of feel. My hybrid is the same loft but it's more like a 5 wood with a short shaft than anything, and the flight is a lot higher and more accurate on bad hits. Plus I can carry it a lot longer, about 20 yards or so.

But my 3 wood is 42.75", as it was when it was stock, despite being only 13 degrees. I have no trouble hitting my hybrid (41/17) off the deck, but the 3 wood is not an easy club to hit high off the deck. That was the one club I was still having trouble hitting off the deck, though it was excellent off the tee, both taking out the left side and getting a good carry. 

So for me, the modern standard works fine as long as I stick to clubs with a bit of forgiveness, CB irons and modern woods. I don't like strong lofts on my irons because I can use the stopping power, but I like them on my woods for trajectory control. It's also very hard to control distance with the long clubs, especially if all your clubs are squished together with 2 and 3 degree loft gaps. The more clubs you can save for your long game the better. Shaft length is relative to your size, but about 42 inches is the longest I can swing comfortably on ground strokes without the fear of a fat shot and I'm 6 feet tall. Don't forget that the RBZ line of woods is also overlength, if I remember correctly. I wouldn't use a 43.5" 3 wood under any circumstances given how hard 42.75" still is to hit. Let alone a 47" driver.

My Wilson Staff Di9s are listed as 5-PW with an AW and a GW.  The 5 iron is 25 degrees they go up 3.5 degrees of per iron, taking me up to a 49.5 degree GW.  That means that my current AW is 1 degree stronger than my old PW.  Depending on how I practice with the iron before I play I'll sometimes take the 5 iron out of the bag and replace it with my 26 degree 5 hybrid on shots of 5 iron distance.  I should probably make that a permanent thing and add another wedge, since my GIR numbers aren't that good and my wedges get more play than they should.