A 2315 is 23/64 and the Griz is 22/64's.  Is the 1/64 larger arrow going to cause the negative impact on penetration in bone that Ashby indicates?  The report seems to indicate it would cause the reduction in penetration.

In the 2 blade head, the Tuffhead is the one I saw that was 23/64 and indicated a 2315 would fit into the head.

Shaft diameter in relation to the diameter of the head is one of Ashby's penetration factors to consider, but it's probably not going to have too much of an effect.  Kinda depends on the size of the animal you are hunting.  If deer, probably no big deal.  If larger heavier game then maybe time to go tuffhead or to a reduced shaft diameter.

I finally got to where I can sharpen the Griz, I really hate to change.  The options do seem clear.  I was hoping for an exception.

I hereby grant you 1 (one) exception to be used as you wish.

Well, according to the talk, that Grizzly will split the bone wide open anyway, so a much larger shaft would slide on thru.

CHuckC

I have always thought the same.  That "S" cut should allow a bit of latitude.

Ashby's test included a modified Grizzly and I did not see an exception noted for the Grizzly.  The post I have seen do not seem to address this issue.  Maybe not many people shoot a 23/64 shaft, so this is not a common concern.  I am sure others have considered this and I wanted to see their experience.