bowhuntn87

hi guys... i purchased a new bowtech SWATa week ago, and i'm trying to figure out the speed roughly without a chronograph. heres the specs: i'm shooting at 70 lbs. my draw length is 31 in.and the total weight for the arrow in grains is 460. the ibo specs for the bow are 314-322 fps. i'm just wondering what kind of speed i'm shooting roughly.

JoshKeller

i'd say between 280 and 285, but I'd say your arrows are a little underspined with the 125 grain heads.

Ed McDonald

I added 10 grains of weight on your string along with the Data you submitted and came up with 292 FPS

http://www.backcountrybowhunting.com/articles/tools.php

bowhuntn87

underspined? care to explain? i thought the guy at the bowshop set me up right with the 7595's.....

TFOX

I agree that your spine is going to be weak.That is the problem with Goldtips.They are rated up to 95#'s but no way in hell will that happen at long draw lengths such as yours.The 7595 is only a 340 spine and you clearly need a 300.


I am getting you right at 280 fps.

Ben / PA

1 question. How long are your arrows? Even with the 125s, you almost have to be leaving them full length to get 460.

TFOX

Not if they are camo,which that was what I assumed,so I could get that weight when I ran the numbers.

bowhuntn87

the arrows are cut right to 32 inches. what do you guys suggest i do to get the spine where it needs to be? i just bought a dozen arrows thinking thats what i needed.

TFOX

Most of us are shooting arrows shorter than our draw length buy about an 1".

You are well underspined.IMO,you will need to be shooting a 30" arrow that is a 300 spine to be close to correct at that poundage.

bowhuntn87

so is there anything i can do with the current arrows i have? turn down the poundage ect ect.?