Bob,
I think a dozen of the arrows are about the same weight or maybe a little more than the bow. I can't find my larger digital scale right now or I would tell you for sure.
I had a good session with the buffalo bow and arrows tonight. Everything went well and the arrows were usually flying to a point near where I was aiming. My brain is finally getting used to the weight of the draw, the mass of the bow, the mass of the arrow, the trajectory of the arrow, and the "instinctive" feel of the hold to make the arrow hit where I want it to at various ranges. I have been trying to practice more out around 25 yards so it will be easier to hit things that are 10 to 20 yards away, which is the distance I plan to be when I shoot the buffalo, if I get the chance. Getting prepared is half the fun.
It is interesting to me that the heavy arrows seem to hit much lower than the lighter arrows, but as I back away from the target the heavy arrows appear to flatten out their trajectory. As I think you said Bob, it must be that the arrows are still rising at the closer distance and are at their zenith out around 25 yards, so it just seems they are shooting flatter. I do know that the arrows are maintaining their velocity very well as one would expect with their high ballistic coefficient.
I really like the tapered design of the Hammerheads (actually double tapered on that model). The design lends itself to a wide range of spine tolerance. I can shoot those arrows out of my buffalo Shrew and my mid-weight bows and have excellent flight from all of them. In the bows that are in the mid to low 40's in draw weight, the tails of the arrows start kicking out to the left (I am right handed) pretty significantly. I have my arrows at 31" and they seem to work for bows down to about 50 pounds. My buffalo bow is just under 70 pounds at my draw of 29 1/2". I am finally getting used to the draw weight of the bow and can now get full extension in the draw. That extra one-half to three-quarters of an inch more that I am getting now versus a couple of weeks ago makes a significant difference in the cast of the arrows. I think my bow is shooting more like a similar bow would that was drawn to 28 inches and 75 pounds. Now if I just had BobW's 32" draw I could really make those arrows zing!
Allan