Arrows are hickory- roughly 800 grains or so. Spined at about 75-80# or so. Don't recal specifics. All bows generally have the same width handle about 1 1/2". Some were a bit wider, others slightly slimmer. All bows shot the arrows accurately, the only difference being at what differecne (to to drop). 55#, 60#, 63#, 73#, and 80#.
I think, and this is just theorizing, that a light physical weighted of the arrow has less mass to knock around off course. Say you have a stiff arrow that's about 300 grains. It would easily fly off the mark. Same with a weak flimsy arrow. But the heavy arrow, being hard to knock off couse, would fly "more accurately" because all the energy is just in getting the miserable thing from the bow. Like shooting a steel pipe from a bow- it just goes ahead. I noticed this from the fact that the Englsih seemed to put more emphasis on weight than stiffness, even after they no longer skewered people.