Depends on the raw length of the shaft and the head weight it was designed for. In some cases, if the raw lengths of the shafts are the same, the shafts may be very similar. The Mitsubishi C6 Black Onyx hybrids shafts and iron shafts are exactly the same shafts. they just have different trimming for hybrids or irons. You can use an iron shaft in an hybrid if you know the head weight of the hybrid, which will determine how you would trim the tip of the shaft. If the head weight of #4 hybrid, for instance, is 240 grams, that is the same or close to the standard head weight of a #3 iron, so you would trim the tip of the hybrid shaft for the #3 iron to accommodate the similar head weight of the #4 hybrid. That is if you wanted it to play to it’s intended flex. Even if you were going to make the hybrid longer in length, you would still trim an iron shaft based on the head weight of the hybrid.
A little more difficult to use a hybrid specific shaft in an iron that takes a .370″ shaft since hybrid head weights are not as “standard” from one type of hybrid to another and they may not have a long parallel tip section length. Just depends on how the manufacturer designed it. You can use a hybrid shaft in an iron, but you need to know what the parallel tip section length is to know how much room you have to tip trim for whatever iron # you are wanting to use it for, and of course the hosel of the iron must take a .370″ tip diameter shaft, which is what most hybrid specific shafts are.
Britt Lindsey