I have a new 8 piece set of miyazaki jinsoku graphite stiff 4 iron shafts, they are all 39″. If I was to install them in a set of STi’s 5-SW and tip trip at 1/2″ intervals (I would not trim the the 5 iron shaft & PW/GW would be the same, SW a 1/4″) would they play close to a regular (butt flex)?
Very difficult to answer as I have no knowledge of that shaft, it’s specs, or it’s build. Trimming from the tip in increments, in theory, will give you the flex consistency assuming the heads progress in weight normally. That also assumes the shafts are parallel tip and have some parallel tip section length to support the tip trim. Other than that, that’s about all I can offer. Just make sure there is enough parallel tip section length to be able to progressively trim the tip as you move from the 6 to 7, 7 to 8, etc.