Shaft size has nothing to do with the threads in an insert or those on a field point or broadhead. With only a couple of exceptions the thread on all are
8X32. There used to be and still may be some around with 6X32 threads, but these were for the very shinny shafts like Easton ACE, so you aren't going to find them unless you special order them.
The only thing where shaft size comes into play is when discussing shaft diameter. Different diameter shafts require different diameter field points, but this has nothing to do with the thread pattern.
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