How will chaning from a 100grain broadhead to a 125 grain change my accuracy? Will it just cause all my arrows to dip sooner, so if I am sighted in for a 100grain tip at 20 yards, maybe just aim an inch higher from the same yardage?
It will not change your accurancy unless you are over or underspined on your arrows. Adding 25 grains doesn't really do much for spine change or kinetic energy. I always ask why guys want to shoot 125gr heads. Many new broadheads are only available in 100gr.
I think it's more of a "macho" thing. With the older heavier vanes you needed a slightly heavier tip to keep the weight center slightly ahead of the actual weight center of the arrow. But now with the smaller, lighter vanes it's not the same as it was. to much weight forward gives a straight flight but lossof trajectory due to arrow dip. too much weight back gives erractic flight. I say to stay with what the charts recommend for your arrow size and spline.but you have to take in the weight and size of your vanes.( or feathers)