Skinny arrow question

[Etter]

So I normally shoot gt traditionals. 400 spine cut to about 28” with 100 gr insert and 200 grain head.

3 rivers screwed up and sent me the xx skinny traditionals. I didnt realize it until I had already cut a few and they will not take them back. I also had to pay the return shipping on the other dozen they screwed up on but that’s another story. Needless to say Ill stick to black widow and big jims.

Anyway, these arrows come with an insert Im guessing is 50 grains instead of 100 but they weigh the same as my normal arrows. If all other things were equal, what is the tuning effect of going to a skinner arrow. Intuitively, I would think they will be stiffer so Id need to leave them longer. What say you all?

[Car54]

Smaller diameter arrows should act weaker, I believe. They are closer to the side plate.

[The Whittler]

Set one up like your regular GTs and see how they work, and tune from there.

[McDave]

Set one up like your regular GTs and see how they work, and tune from there.

I think this is the best advice you're going to get on this.  One would think that a spine designation: 400, 500, etc., would be the same across brands, but my experience is that they are inconsistent, even among different models within the same brand.  Sometimes this can work to your advantage, where you can't quite tune the arrow you had in mind the way you wanted to tune it, but a different brand of shaft with the same spine designation tunes perfectly.  And it's not always that a skinnier shaft will tune weaker or stiffer than a wider shaft; it can go either way.

Since you're stuck with them, you might as well try to make lemonade out of the lemons and see if you can get them to work for you.  You may even get to like them better.  I'm surprised, though, that 3 Rivers would not pay return postage on the ones that you hadn't cut, if they sent you something you didn't order.

[M60gunner]

I would start by using the 3R spine calculator and playing with arrow length, insert weight and point length. I did this recently with some Beeman 500 spine I wanted to try from my 45# Bear Mag TD. Know you riser specs, cut to center or be on. In my case I needed a 29”shaft, 100 grain insert and 100 grain point. Actually they are only a few grains heavier than I wanted but they shoot just fine.

[Wheels2]

I would say that is on 3Rivers...
I have never had an issue with them and based on their reputation, it surprises me that they won't take them back.
Hopefully they see this post and reconsider. 
They get a lot of business off of this site members.
Another avenue is to file a complaint with your credit card company. 

[katman]

If total weight is same they should shoot weak due to closer to centershot as mentioned.

"I also had to pay the return shipping on the other dozen they screwed up on but that’s another story"
Very interesting, will keep this in mind when ready to order shafts.