You can ream out the heads and give yourself more options, but there are a couple of .355 A flex shaft options. AeroTech makes the SteelFiber 70cw in an A flex (AT0020i) and Nippon makes has the Zelos steel in .355 in an R2 flex, which is like an A flex. If you decide to ream out the hosels, we recommend using a reaming and boring vise with a drill press of some kind. this is the only way to insure a truly square bore. REaing with a hand drill can be done, but it is less precise. The reamers are more for cleaning out than boring our. If you are going to bore out, you would need to stpe drill, starting with a "T" size bit, then moving to a "U". This will get you to .368. You could then use the .370 reamer, or could move to a 3/8" bit size to get the hosel to a .375", which is OK for use with .370 tip shafts.
Date published: 2015-07-08