ORIGINAL: LouisianaTomkat
500 grains is 500 grains, whether it is 1 mm wide arrow or 2" wide arrow.
You are kiddin' right? If an one arrow is wider than another, there is more surface mass (Not weight mass). If the same "weight" arrow has more "surface" mass it will take more KE for a pass thru.A smaller "surface" mass arrow, will out penetrate a larger "surface" mass arrow of the same weight every time. This, considering you do not have a 2" cutting surface trying to plow all the way thru a deer's body. I am speaking of using Fixed heads.
Sorta like trying to shove a greasy BB up a Bull's ass compared to shoving a bowling ball up same said Bull's ass. It will slide in a lot easier if it is smaller.
LT
Seems to me that if your broadhead has cut a path for it, the shaft diameter isn't an issue anyway. Besides, the overall difference in hunting shaft diameters is, in reality, minimal. I'm assuming, of course, that no-one is hunting with X-Cutters.