dimmishing returns start at what bow weight?

[Raging Water]

Originally posted by pdk25:
I just wish that someone would quantify it a little better.  This has been posted on a bunch.  Does going up from 60 to 70# give you 90% of the gain that going from 50 to 60# does?  Is it less/ more.  I know that it will be different for each model of bow, but there should be some data out there.  Saying that you don't gain much is such a relative statement.  I know that you don't need high poundage for North America, but acting like there is no difference in performance for a ten pound jump isn't right either.

3 questions:

1) If a 60# shoots a 600 Gr Arrow at "X" FPS. Then, would the 70# Bow shoot a 600 Gr Arrow at greater FPS?

2) If a 60# shoots a 600 Gr Arrow at "X" FPS. Then, would the 70# Bow shoot a 700# Arrow at "X" or "Y" FPS? Would it still be "X"? No Change in FPS?

3) If a 60# bow exerts “X” amount of force, would a 70# bow exert “X” + 10? Or would diminished returns set in and the 70# bow exerts “X” + 9? Or “X”+ 8? Or “X”+ 7? Etc?

Matt

[Charlie Lamb]

Perhaps Kikk, Sixby, and other bowyers on this forum could give a comment.There are a lot of personal answers but none from the experts, without expert input, everything else is speculation,.
 

I pay attention to what the poster at the top of the page says. His handle is Bowbldr for a reason.

[RC]

My shoulder and neck DON`T hurt anymore due to loving 48 lbs and less the last few years.
  Good question but no need for brain straining for me on it.RC

[elkbreath]

I'm not sure on where the diminishing returns start exactly.  seems 60-65 is consensus.  Though, I do find it oddly ironic to also be the limit where most people start saying that we are now pulling 'tooo much bow' to be 'comfortable' or accurate.

We need to remove the 'overbowed' feelings from the equation, because they are emotionally charged and entirely relative.  

I think matt is on to something, because its partly a paradigm issue.  The verbage of the question itself is dependent on definition.

His question is the one that is relevant to me.  In other words, in real word shooting (the first 50-80 arrows), I feel every bit as comfortable shooting 60# as I do 80#.  As such to me the "diminishing" point of return I am concerned with is the point where the extra pounds no longer produce more momentum.  At any time there is a relative gain in momentum, I'm interested.    

It makes sense to me to shoot a lighter bow, say a static tip recurve, that will produce the same momentum as a heavier bend in the handle d-bow, providing you can get such a bow quiet.  

However, given all things equal, like accuracy and point of impact, I'll take the heavier weapon as long as it produces a gain in penetration power.  


Dan

on a different note, IME, it also produces gains in speed because as I increase in weight it is more difficult to get over 11 gp #...  but that is a relative thing again since I am favorably changing a variable.

[elkbreath]

The other thing, if we are talking 'gains' then we Are speaking of a peak, not a plateau that drops off. A 1# bow won't be very efficient in relation to limb weight.  

And every bow and archer combo would produce a differing peAk. Finding that spot would be exhausting on so many levels.  For the individual archer/bow combo it may be doable, but who would have the Money to obtain all the Correctly spined arrows to go through the various combos?  Not to mention the theoretical changes of other factors like arrow style and FOC...

[duncan idaho]

Your are correct, Bob Morrison is an expert and I respect his opinion. Good discussion for those that shoot bows over 60#.

[Bear Heart]

I started a thread on this a couple months ago.  Look it up in the search.

[Mojostick]

OK, I'll answer it...41 pounds.          :D      
I'm getting passthru's with 40lbs, so I'm not sure how much further I need my arrow to go once it passes thru the deer.

[woodcock]

I am in full agreement with Mojostick.  Don't understand question really. Way too many variables. One thing I believe is that a #45 bow overdrawn to 30" producing an estimated #51 of actual draw weight (if that is your draw length) is more efficient than a bow of #51 drawn to 28".  But I know a 40-45 lb bow is deadly on deer and black bear.  See youtube video of tracy shooting a bear with #39 zipper bow.  Full pass thru and bear was moaning dead on audio within seconds! Bottom line is, shoot as heavy as you are happy with and capable with.  More important is matching arrow weight to maximize effectivness of bow.  More important yet is hit 'em right!!!!

I have had heavy Hill style bows that were slow and some that were faster than the slow ones at the same poundage, but my 64 pound Legend Schulz was as fast with the same arrow than most of the heavy weight bows and the same draw lengths.  I tried drawing the the heavy slow ones an inch or two further and was surprised what I found. Those slower heavy bows did not change as much with varied draw lengths as my 64 pound Schulz longbows which in turn did not vary as much in cast per draw length as my fast takedown BW recurve. So from that I assumed that part of the hunting success that I had from the heavy longbows was that I got a very predictable arrow flight even if at times I may have short drawn from nerves or drew long from adrenalin. A heavy draw heavy limbed longbow has to move less of that heavy limb at a shorter draw and more of it at a longer draw, static hysteresis.  I do not believe that the equation works the same with recurves as the limbs function differently.