I need to make a decision regarding arrow shafts.
I shoot a longbow---56 # draw @ 27 in.
My present arrow are CE 100's---cut to 27 7/8 inch with 3 grain/inch weight tubes. The charts say they are underspined, but a trial of stiffer shaft was unsuccessful. These bareshaft well with 200 grains heads, and broadheads of the same weight fly well and hit to same point of impact. The complete arrow weighs 498 gr: that works out to 8.9 gr per # draw.
The balance point is 8 3/8 in. behind the point and 19 1/2 in front of the nock throat.
Wanting a heavier arrow, I bought some 8 gr. /in. weight tubes to try, and they increased the weight of the bare shafts by 130 gr. I thought they were stiffer than the 3 gr tubes, and rigged a field expedient spine tester to prove they were, so I figured I would need to increase the head weight. Instead I found that I had to drop to 150 gr to get good bareshaft flight. ( I can only hypothesize that the additional mass in the front of the shaft overshadows any effect on spine by the stiffer weight tube).
So the net effect is a total arrow weight 583 gr = 10.4 gr/#draw.
I think I can work with that, but the balance point is moved exactly 2 inches aft: now 10 3/8 in is in front--17 1/2 is in back.
Sooo--- will the loss of FOC negate any penetration gain from such a minimal increase (17 %) in total weight?
Or do I give up and spring for Grizzly Sticks and see if I can load up enough mass in the front to get them fly?