The Adams A12 Pro or the Adams A12 OS iron heads have more than a 1/2 " bore depth. The depth of the hosels should be at a minimum 1.25". Generally, you do not want the iron shaft to to be installed in bore depths of less than 1.25". Check the hosel bore of the head you are referencing to be sure there is not an obstruction (old epoxy, tip weight). Again, the bore deph should be at least 1.25".
Date published: 2017-03-06