arrows weight vs. speed

bowhuntinnut · May 28, 2013

Question;

I am shooting Easton Axis arrows, 300's which are 11.5 grains per inch. Is there any way to know how much speed I will pick up for every inch that I cut off of the length?

Thanks

BigPig · May 30, 2013

The more important consideration is spine. Changing arrow length will affect your dynamic spine. That has far more impact on accuracy. You won't notice 10-12 grains of weight difference at normal ranges inside of 60. You will notice 20-24 grs of difference.

GeorgeE · May 30, 2013

As BP said...Also, Easton has some great programs on their site to help you!

'Ike'

bowhuntinnut · May 30, 2013

In other words, nobody else knows either!! Thanks anyway guys!

BigPig · May 31, 2013

LAST EDITED ON May-31-13 AT 09:00AM (MST)[p]>In other words, nobody else knows
>either!! Thanks anyway guys!

>

No, that is not it at all. There are a multitude of archery calculators online that will likely give you your exact answer if you want to waste your own time. My point is that sounds like you are missing what is far more important. If your setup is shooting well now, don't mess with it in an attempt to gain a little speed. Speed means so very little. Cutting 2" off your arrow will dramatically stiffen spine and may considerably effect accuracy. That is far more important. IMO, losing any accuracy is not an acceptable tradeoff to gain a little speed. It will also lose weight and thus, momentum. Again, not a good tradeoff IMO. Chasing speed often creates more problems than it solves.

bowhuntinnut · May 31, 2013

Yes i understand your point. I have been shooting a bow for well over 20 years now and am not chasing speed! My world revolves around KE and accuracy! After quite a while poking around on the web i did not find an answer to my specific question so i posted it here in hopes that maybe someone could help me with that SPECIFIC question! As i said before it does not appear that anyone else knows the answer to my question, but thanks for trying to help!

31incher · May 31, 2013

>Yes i understand your point. I
>have been shooting a bow
>for well over 20 years
>now and am not chasing
>speed! My world revolves around
>KE and accuracy! After quite
>a while poking around on
>the web i did not
>find an answer to my
>specific question so i posted
>it here in hopes that
>maybe someone could help me
>with that SPECIFIC question! As
>i said before it does
>not appear that anyone else
>knows the answer to my
>question, but thanks for trying
>to help!

31incher · May 31, 2013

>>Yes i understand your point. I
>>have been shooting a bow
>>for well over 20 years
>>now and am not chasing
>>speed! My world revolves around
>>KE and accuracy! After quite
>>a while poking around on
>>the web i did not
>>find an answer to my
>>specific question so i posted
>>it here in hopes that
>>maybe someone could help me
>>with that SPECIFIC question! As
>>i said before it does
>>not appear that anyone else
>>knows the answer to my
>>question, but thanks for trying
>>to help!

He did answer your question thou. Stickem archery has a eebsite that has calculator you could figure it all out pretty easy.

Jestanw1 · Jun 2, 2013

10 grains approximates to roughly 3 fps, I think that's what you're asking? There are a lot of factors that go into it but that's a close estimate. For instance I just added 50 grain weights to the front of my arrows and went from a 395gr arrow shooting 319 fps to a 445gr arrow shooting 303fps. The heavier the arrow the more fps you will lose or gain per 10 grains.

Headneck418 · Jun 23, 2013

the answer you are looking for is an approximation and in that every 10 grains one way or the other you will either gain or lose 3FPS either side. the question you need to ask yourself is what is my effective range and is my set up dialed in. If so, you are entirely too close to the season to be making any significant changes to your set up if you are shooting all the time. IMO The pinnacle FPS of arrow flight is somewhere between 270-290 depending on your set up. I personally like to shoot the heaviest arrow possible for my set up and effective range. KE is the biggest factor to take into consideration and the above comment about the spine dynamic was right on. Every bow will shoot different, as its based all on the shooter and the form, grip etc. Hope this helps

shedcrazy · Aug 26, 2013

great replies! momentum is key. I read several Ed ashby papers and it changed my whole setup. I would recommend to OP to read his stuff before cutting up your arrows in an effort to increase speed.

ILikeElk · Aug 28, 2013

The answer to your question is there is not enough information to answer your question. In order to truly answer, one would have to analyze ALL the force vectors acting upon your arrow. The only vector I can accurately surmise from the information you've given me is gravity (9.8 m/s^2). Helpful information would include starting mass, starting velocity, angle of travel. Even then, the true answer would be difficult to obtain, because of reasons already discussed, dynamic spine, for example, will continuously affect how each vector acts upon the arrow, except little g of course. Not to mention that will change from shot to shot, creating a true answer for one instance, but not every instance.

It's just physics...