Poundage vs. FPS on a modern compound

[CodeMonkey]

Long story short, it looks like my limbs are in need of replacement due to my lack of surefooted-ness.

Limbs are 65lbers because when I bought the bow (Hoyt Helix Ultra) I could barely draw 55lbs. Say I move up in poundage to 70s or even 80s (this whole archery thing has forced me to get in shape), how much FPS can I expect to gain?

Edited to add: I draw 30'' and am using the maxed out #2 cam

 

[Mighty Mouse]

2.5 fps per pound is a reasonable rule of thumb.

FWIW below are qSpine's speed predictions for a hypothetical 500 gr arrow out of a Hoyt Helix Ultra (334 fps IBO, 6.75" BH, 34" ATA, 80% LO) at 30" DL:
268 fps at 65#
291 fps at 75#

 

[Vandal 44]

I am of the opinion shoot what's comfortable. If you can comfortably pull 80 pound while sitting on a stool then go with 80 pound limbs. Speed would not be my primary focus.

Wish I could pull 80 pounds, hell wish I could pull 60 pounds but with bad shoulders I have to be happy with 55 pounds. With my set 55 pounds, 30" draw and a 445 grain arrow I have killed everything from elk, deer and bear with this my set up.

 

[Rich M]

Ive got a bum shoulder and shot archery from the age of 7 thru 40’s somewhere. Was shooting 70# at 12 years old. Not saying it messed up my shoulder but cant say it did not factor in.

Stay as low as you can for what you are hunting. Bigger isnt always better.

 

[Billy Goat]

It's convoluted. I can get a 50# bow to shoot within about 5-6 fps of a 65# bow. If you are shooting at the 5 gpp threshold then they are all going to be pretty close.


If you are shooting say a 420 grain arrow at 55#, then go to 65#, well, you will gain close to 30 fps, but if it was spined for 55#, you will need new arrows that can handle the poundage.


So if you are set on a certain weight arrow, you will gain speed. But if you always shoot around 7grains per pound, you won't notice any difference.