Hey MT, back in my younger days, I used to live in Seeley Lake! I love and greatly miss Montana.
I’m no expert, but maybe I could offer a little advice. Please excuse my way of analyzing your problem, it’s just the way my brain works, and plus I’m not proficient at typing. So here we go!
So, I'm shooting my new Miller old Tom, and I just switched to woodies,
my opinion: I’m a carbon man, but have several sets of woodies myself.
I'm getting my inward down feather hitting the shelf and wearing them out ( pieces coming off the feathers) the arrow tail is hitting the shelf.
my opinion: Sounds like to me, that your nocking point is a little low.
My previous carbon beman MFX carbon classic 500 traditionals are not hitting nearly as bad.
my opinion: But they are hitting wright? Remember, you have went from a diameter of 9/32 to 11/32 or greater.
I did not change the nock position yet, I did try raising the arrow nock above the nock set to get the tail higher off the shelf but it hit worse, right now I'm set about a full quarter inch high nock.
my opinion: Set it at .625 to .750 minimum to .750 to .875 maximum.
If I go above my nock point with the arrow I'm about 1/2 inch tail high. I shoot standard split finger, and I have a nice inline release and elbow position.
my opinion: If you move your nocking point up to where I suggested, and you still getting bad arrow flight, it could be your spine weight.
What do you think the issue might be, the woodies are from Bob at Whispering Winds Arrows and are spined for my bow. They are sweet arrows!
my opinion: Just because they are spined for your bow weight doesn’t mean they are spined for your bow. The governing factor is how your riser is cut in reference to the center line of the bow.
Hope this helps.
And by the way, this is only my opinion, I could be wrong.
Good luck!