I chrony'd my Mohawk today:
125gr Tips swaged onto Cedar Arrows (520gr total weight) - 140/145 fps.
175gr Field tips screwed into GT 5575s (460gr total weight) - 165/170fps.
If I drop the 5575s down to 435gr, or bump them up to 485gr: Can I conservatively expect to gain/lose 15 fps ~ for a 25 grain gain/loss difference in weight?
Thanks.
It depends on your bow weight. You can figure 10 fps for the differance between 8 gpp and 9 gpp and 10 gpp etc. Example, If your bow shoots 180 fps at 10 gpp it will shoot about 190 fps at 9 gpp. Hope that makes sense.
zwickeyman
Intuitively, that makes sense. My two samples from yesterday (for a 55lb bow). I lost 20 fps by increasing 1.09 gpp.
145 fps @ 9.45 gpp
165 fps @ 8.36 gpp
The heavier arrow was Cedar, the lighter arrow was carbon with a more weight forward balance.
They are both spined for the bow; I guess I didn't expect that much difference between materials.
Thanks.
I have found that carbons of the same weight as wood or aluminum fly faster. Don't know why.