I'm guessing that the insert length would affect overall spine of said arrow. I have some long 50 gr alum inserts and some shorter brass. Arrow with longer insert should be stiffer. Or is this just splitting hairs? Thanks guys
Most of the bending occurs in the middle a little length won't have any effect at the tip; but weight will.
What Bjorn said!
I was thinking that a longer insert actually "shortened" the bendable part of the arrow.