One thing to add, and the reason you should never cut a shaft to a playing length without it being either dry fit or actually installed into the heads, is that bottom of the bore to ground line dimensions can vary from club to club in a set. Could be a variation in the bore depth, the sole radius, etc. that can cause variations. So if the #6 iron has a bottom of the bore to ground line dimension of 1″, you can’t assume all the clubs in the set will be exactly the same. One might be 1 1/16″, another 1 1/8″, etc. An 1/8″ variance would be unusual. Still, there can be these slight variances.
Britt Lindsey
Excellent point, Britt. We also cannot assume the lie angles are correct from club to club. That also affects finished length.
When I build a set, I make sure each lie angle is correct for the golfer before I establish the length I need for each club.