Carbon arrows weigh just the same as aluminum. Some, in fact, are over 11 grains per inch. The difference is diameter. THey get the same weight with smaller diameter, decreasing resistance and INCREASING penetration. I would also bet an out of tune bow, or just too light an arrow.
Simply incorrect! It takes a bigger diameter heavy walled carbon to come close in weight to a smaller diameter aluminum arrow.
Kind of late in the thread to be asking this question , but what kind of setup do you shoot?
What bow , poundage , draw length?