figuring FPS

[farmerman99]

Does anyone know if you can take, #'s of pull, length of pull, and weight of arrow and figure approx. FPS

[Holy Smokes]

Originally Posted by farmerman99

Does anyone know if you can take, #'s of pull, length of pull, and weight of arrow and figure approx. FPS

seems reasonable nuff
I just ain't a mathmatictican

[J.C.]

Originally Posted by farmerman99

Does anyone know if you can take, #'s of pull, length of pull, and weight of arrow and figure approx. FPS

yes, if you know the IBO speed of your bow.

[red44]

Long winded, but I've seen 2 methods posted on other sites.
#1
start w/your bows IBO rating. (70/30 w/350 grain arrow)
for every inch less in DL, subtract 10fps
for every 5 lbs less (from 70), subtract 10fps
for every 3 grains over (350), subtract 1fps
for every 3 grains on the string, subtract 1fps
#2
shoot a group at 20 yards with the 20 yard pin, mark the center of the group
do the same from 40 yards (using the 20 yard pin)
the distance between the centers of the groups give approximate fps
difference......approximae speed
28.7.............220
24.2.............240
20.6.............260
17.7.............280
15.5.............300
13.6.............320
12.8.............330
No idea how accurate these methods are, never tried it, but I did copy the info down for "some day".

[tnts79]

There is a calculator on the internet that is very accurate. I can't remember the website, mabey someone else can??? I'm sure Bunnyman has it as one of his favorites! I just looked in my favorites and guess what?!!
http://bucklemke.com/ke/ke.php
I am shooting 280 through the chrono and this put me at 276... good enough in my book for a calculator!