I guessed that it probably was. The only problem is that when building arrows of different weights, it's very difficult to keep thing equal. Althoug K.E. changes very little with different different weight arrows, the penetration potential can change drastically in some situations when increasing momentum, spine or F.O.C.. It would be my contention that very few people are limited by K.E. if they have adequate momentum, spine, F.O.C., blade design, blade sharpness, etc. Those that are truely limited by low K.E., would be better off paying close attention to almost everything else. In ohter words, take what working potential the arrow has, and put it to work in the most effective way.