I have heard lots of theories on this,, heavier ggp shooting better from certain types of bows,, some say the wierd bow with 4 limbs,, Penobscot,, shoots heavier arrows better than normal self bows, but again,, I never see any real documentation,, I think since most of us have no need to shoot heavy arrow not much research or testing is done,,, I am the same way,, I feel like if the bow is shootig great with 10ggp,, I usually dont test it with heavy arrow,, I may hunt with a heavy arrow but just assume since the bow shoots the lighter arrow well,, it will shoot the heavy arrow well too,, and rarely chorongraph the heavy arrow,, I do hunt with a 700 grain arrow quite often,, from my 50 to 60# self bows,,they fly nice, ,just dont know how fast they are going,, I would guess that with most bows, the bow shooting the best at 10ggp,, will shoot the heavier arrow the best, ,but in archery things can be counter intuitive so I am staying open minded,,