Originally posted by acedoc:
I ran into some tuning issues due to a long draw and heavy bh. One of the options I came up with was to add wt to nock end. Apparently small increments at nock lead to large tuning changes
That's correct, about a 2/1 ratio. In other words, 20 extra grains on the back stiffens the spine about as much as 40 grains on the front weakens the dynamic arrow spine. Gold Tip has rear adapters that are made for the purpose. I have used them with good results.
That said, I think I'm about the only one who likes them, so YMMV. Other people have complained about the effect on arrow stability and from a hunting perspective, the effect of weight on the rear is contrary to the positive benefits of EFOC. In other words, weight up front helps with penetration. Weight in back might help too, if you have a perfectly straight hit. If you have an angled hit, weight in the back might actually retard penetration by bending the arrow more in the direction of the angle.