Diminishing returns

[Bear Heart]

I talked to a bowyer who said after around 53# the returns in performance get less and less for his bows.  Any thoughts on this?

[Caughtandhobble]

Well I can see what he is saying, it's all about less mass for serious performance. Some bowyers have figured out how to add stability, structure, repeatable accuracy with less mass. But let's face it, 53# is plenty for most game. A well tuned bow and a sharp broadhead equals meat in the freezer.

[Frenchymanny]

Can we know who that bowyer is?

     

F-Manny

[robtattoo]

Seems like the kind of bowyer I'd like to avoid. Who is it?

[beachbowhunter]

That a common sentiment that I have heard/read about. Usually they say it starts around 60#.

[59Alaskan]

What is the definition of performance in this context?

[Bill Carlsen]

Jack Howard, If my memory serves me  correctly, said that 60# was the point he considered diminishing returns kicked in.

[duncan idaho]

There are serious design problems with a bow that has "diminishing returns" after 53#.

[Cyclic-Rivers]

The Bowyer should know his bows.  Listen to his suggestions if you are ordering from him, then order what you want!

The idea of diminishing returns with bow weight is something I have not thought of before but seems to make sense.

Curious but I would think....  If you add mass to the limbs they will essentially become "slower". as energy is absorbed back into the bow instead of the arrow.

Look at the body building competitions. those guys are huge and have a lot of stored energy to "work". I wouldn't want to get punched by one but Don't expect them to run the mile in 4 minutes.

For me it would be about finding a happy medium.

Not saying its good or bad but you must weigh your options. A bowyer who knows his craft can help you with your decisions.

[gringol]

Trad bows can't cast an arrow much faster than 190fps regardless of draw weight, so with regards to arrow speed diminishing returns should be expected.  Heavy bows gain power by having the ability to cast a heavier arrow not by casting it faster.  Heavy bows have that ability because the limbs are heavier.  The point is, make sure you are clear about what the bowyer is refering to.  If he is saying he can't get any more speed at high draw weights, don't sweat it.  If he is saying he gets less efficiency you should worry.  Gpp/fps should be similar regardless of draw weight.

[Bear Heart]

It is possible I got the poundage wrong but not the idea.  It was the son from Toelke.  He didn't say you wouldn't get any benefit from heavier draw weight but that it would not have the same effect as each pound gained in the lower weight spectrum.

[Bear Heart]

Originally posted by gringol:
Trad bows can't cast an arrow much faster than 190fps regardless of draw weight, so with regards to arrow speed diminishing returns should be expected.  Heavy bows gain power by having the ability to cast a heavier arrow not by casting it faster.  Heavy bows have that ability because the limbs are heavier.  The point is, make sure you are clear about what the bowyer is refering to.  If he is saying he can't get any more speed at high draw weights, don't sweat it.  If he is saying he gets less efficiency you should worry.  Gpp/fps should be similar regardless of draw weight.

I didn't even think about the fact that a heavier draw weight would be accompanied by a heavier arrow if you to keeping the same grains per pound ratio.  I can imagine that given that assumption heavier limbs would move a little slower but have more energy stored in them.

[pdk25]

I don't know the numbers, but dimishing returns is far different than no returns.  If going up 10# from 70 to 80# gives you 90% of the performance gains that going from 60 to 70# does, well that is still quite a bit of a difference.

[maxwell]

Good one Pat- I wonder what the % really is??

[BUFF]

I shoot a 570 grain arrow from my 55 pound bow.
I shoot a 630 grain arrow from my 64 pound bow
I shoot a 780 grain arrow from my 74 pound bow

The cast is pretty much identical..

I swap back and forth between them and the arrows hit right where I'm looking

[oxnam]

Changing  from 30 to 35# is a 16.67% poundage increase.
Changing  from 45 to 50# is a 11.11% poundage increase.
Changing  from 60 to 65# is a 8.33% poundage increase.

Using a set weight increase, ie 5#, the percentage of weight increase does decrease as bow weights get heavier (amount of the increase divided by the original amount).

If an archer goes from a 40# to 50#'s, someone shooting a 60# bow would have to jump to 75# to match the percentage of weight increase of 25%

I guess it just depends on what someone is really trying describe.  Shoot what's comfortable but there are advantanges to shooting a heavier well designed bow.

[pdk25]

That is only telling what the percent poundage increase is, not describing a change in the linearity in the amount of energy stored/delivered per pound increase in draw weight.  At least that is what I thought the topic was referring to.

And I agree, there can be advantages to a heavier bow.  It's just that it probably doesn't matter much for most people when they are hunting deer, turkey, etc..

[mahantango]

I also remember that study by Jack Howard. He did a fair amount of testing using a shooting machine, and determined that around 60# was the most efficient weight and beyond that returns began to diminish. As I recall, he was primarily concerned with velocity.

[Archie]

I assumed that this thread was referring to the force with which a bow throws an arrow, that the more 'muscle' a bow has (i.e., weight), the more that 'muscle' (limb mass, internal friction, whatever) begins to inhibit the bow's efficiency.  As in the case of an olympic runner, who doesn't want excess muscle to slow him down, the 'diminishing returns' scenario is one of balancing raw power with efficiency.

[pdk25]

Yep, I believe that is it. The only difference being that there is no reasonable point in time that a heavier bow won't outperform a lighter one.   I would still like to know how much, percent wise, that efficiency is lost as weight goes up.