Speed loss per pound??

[ka]

If you have a bow that shoots ....say 190fps at 50lb and you dropped down to 48lb with same weight arrows ,everything the same other than the poundage .how much velocity would be lost???

[GMMAT]

I'm guessing 2fps.

Same bow....virtually same arrow.....I gain 10fps. when switching from my 52# limbs to my 58#'ers.

[vermonster13]

In a perfect world 7-8 fps.

[GMMAT]

7-8fps with TWO #'s of DW?

Man....I need to talk to Dave at Schafer!....lol

(I'm not laughing at you, Vermonster.....just joking)

Would it work differently if he were adding an inch?  Say...going from 48-50#?

[zwickeyman]

2 fps per #    so 4 FPS

[James Wrenn]

Yeah 2 to 4 is about right on most bows.You get about 1.5-2fps for every lb you draw on most bows.If by reducing weight two lbs it allows you to draw the bow a bit farther you might gain some speed.Many people that are on the verge of being over bowed have dropped weight 5lbs to something they could handle better and picked up performance because they quit creeping on release.

[vermonster13]

The reason I said "in a perfect world" 7-8 fps is because 2#s on a 50# bow is 4% of the energy stored in that bow. Now do the math    

Of course it's never that straightforward or linear because of other factors.

[George D. Stout]

Exactly.  If you drop two pound, and gain a 1/2" of draw, you won't lose any and may gain.  There is not pat answer, it will be different with every bow and every person shooting it.

[ka]

Thanks for the info.!!

[excelpoint]

On my Jim Jones Firefly which is 60#@28 and 58"amo I lost an average of 1.9 fps per pound when running a bunch of different arrow weights through the chrono at both 28" and my 26" draw. I shot all arrows a minimum of 3 times through the chrono at a measured 26" and 28". The bow was measured right on 60#@28" and dropped to 51#@26"