Is there a point of diminishing return?

[shortstroke 91]

I figure with all the testing that's been done and the wealth of knowlege here someone might know. I'm shooting a full length GT 35/55 with a 100 grain brass insert and a 250 grain head out of a #40 recurve. My total arrow weight is 660 so I'm looking at 16.5 GPP and a 23%FOC. I mostly hunt deer with the occasional hog thrown in.

My question is if there's an area of diminishing returns with arrow weight on a light bow, such as if you get over 14-15 GPP then the momentum you're gaining from weight is outweighed by the speed your loosing.

Just a thought, I'm not looking to change anything. My arrows are hitting right where I want them (most of the time) and my POI is now 27 yards (perfect for my hunting). Only complaint is that they do drop in a hurry.

Thanks to any and all

[Bowwild]

Surely there is such a point but I don't know where it is and I'm not anywhere near it.  I'm going to try to boost my arrow weight about 100 grains for the 2011 hunting seasons.  This will put me around 11.2 GPP. Although, I have no complaints with my penetration on white-tail deer at 9.02 GPPs this year.

[SteveB]

I hunt with around 53# recurves.
16gpp is way past what I would use.
I like the combo of trajectory, quietness and proformance on game at at around 9gpp

[YORNOC]

Absolutely can blow the whole thing, but I dont know of any formulas myself. You may be the pioneer here with that particular setup, let us know if you find anything if you experiment after the season...

[larry]

much past 13 gpp and you're at the point of diminishing returns

larry

[bgremill]

This is a very interesting question that you ask.  I could swear that I read an article in either in TBM or on here once where someone did exactly that.  They had a 40# recurve and tested penetration and bow noise with arrows weighing 320gr through 640gr or something.  If my memory serves me correctly, the bow noise and penetration improved greatly until 9gpp then hit a plateau at around 10gpp or 12gpp.  I'm sorry I can't recall any better than that.  I do remember thinking to myself how funny it was that all of these guys and gals from TradGang were making these crazy EFOC and ultra heavy arrows based on the Ashby information; and, this one test showed that the old 9-10gpp standard still proved to be best.  
If someone else has access to the article, I might need to be corrected.  I'm trying to give you the best info I can based on my memory which I would not bet on.
Please don't take this post as though I'm taking a position contrary to your belief to shoot heavy, EFOC arrows.  If they shoot well for you; and, you feel more confident with them, then they are the best for "you".  That's all that's important.  
I can't imagine a 450gr or 500gr arrow not penetrating a deer or a hog shooting less than 20yds.  If the hog is 350+#'s with a 3" thick shield and another 3" of mud caked on the shoulder and sides from wallowing, DON'T SHOOT!  That's pretty simple and easy to overcome.
Have you tried arrows that are not so extreme and had them fail to penetrate?

[Fischman]

I shoot an 850 grain hickory arrow out of 66 # cascade and i agree with larry if you get much more than 13 gpp you start loosing any advantage especially in trajectory at longer ranges. That being said if it works for you and your arrows hit where you want and inside your effective range, they should be extremely quiet.

[Hud]

If you look at the equipment used by Saxton Pope, Art Young, Howard Hill, Fred Bear and others, you are probably right on. For example Fred Bear used an arrow that was 9 x 65# = 585 Gr. It may have been higher, but not much. No special weighting or FOC on most of their arrows.

I agree, much beyond 12 gpi is not necessary for most game, that does not mean a high FOC is not desirable. You get maximum penetration with the higher FOC, but there is a point where distance is lost when approaching extreme FOC. How much is too much is a matter of personal choice.

[Huntschool]

Wow, thats a ton of weight with a 40# bow. I would think ya could drop that arrow from 12-15 foot up tree stand and get damn near pass through... LOL

I also am sure that there are likely some calculations out there to "indicate" a down turn in the performance curve but I am no math guy.

As others have said, if you are happy with the setup go with it.

I am a bit stuck at between 9-10 gpp with sharp BH's and good FOC...  Works for me....

[WESTBROOK]

I think its been said that a bows efficiency peaks around 11-12 gpp.

I try not to get cought up in the numbers game, every bow is a little diferent but each one has its optimum setup and you know it when you find it. That combination of speed/trajectory, arrow weight and quiet, when every thing just feels right. I'm not very smart so it usually takes me a while and its usually by accident that I find it.

Eric

[Night Wing]

I shoot very heavy GPP arrows out of my two low poundage bows. My 42# recurve is so quiet, there are no string silencers attached to the bowstring. No limb hush puppies silencers either.

There are other factors involved that aren't being mentioned. The design of the bow comes into play with regards to trajectory and heavy arrows. As an example. Take two recurve bows of the same model that are 66" long in length and both are 42# @ 30". Both bows are shooting 12 strand Dyna97 bowstrings with 7 9/16" brace heights. Now comes the interesting part. The first recurve has a riser that is 19" long with 23.5" limbs. The second bow has a riser that is 23" long with 21.5" limbs. Throw into the equation a heavy arrow weighing 637 grains which equates to 15.16 GPP. The bow with the longer limbs will cast the heavy arrow with less trajectory drop at 20 yards than the bow with the shorter limbs even though both bows are 66", 42# @ 30".

Since I shoot low poundage bows; I wanted a quiet bow, great penetration with a very heavy arrow and very little arrow drop (trajectory) between 10 and 20 yards. These were my three deciding factors. Arrow speed was not a factor. Hence, my 637 grain 2117 arrow preference. My preference in recurve bows is short risers and long limbs. This is why I shoot 66" Blacktail bows with 19" risers and 23.5" limbs.

BTW, my 42# recurve shoots a 32", 637 grain 2117 aluminum arrow around 153 fps with 15.4% FOC.   As a sidenote; if I shot a 32", 560 grain 2213 arrow, which equates to 13.33 GPP moving along at 162 fps with 16.2% FOC, I would need to put string silencers on the bowstring since the bow was noisy upon arrow release and the penetration at 20 yards was far less than that of the 637 grain 2117 even though the 2213 has a higher FOC number and greater fps number. I attribute this to the quirk of shooting aluminum arrows with different diameters.

[YORNOC]

Night Wing, excellent input...it goes to show you just have to experiment with your own setup. I'd like to hear from some 65# and up guys at how different their max point would be. I shot a 76# Silvertip(64") with Grizzly Stiks and a 200 grain STOS with brass inserts and a steel screw in adapter for my bison hunt. The steel insert made all the difference, as soon as I tried it everything clicked. I don't remember the numbers, wish I did...but I know the finished arrow was just over 1000 grains at 31". They flew out of that bow as smoothly as many of my target setups.

[Gehrke145]

I shoot bows in the low 50s and never shoot over 450 even on elk.  I just don't see the need.

[shortstroke 91]

Wish I had a chrono. I have several arrows that I can shoot from this bow that vary from 450 grains up to the 660 I'm shooting now. If I knew the speeds I suppose I could figure out the momentum of each and find the most efficient one (not including foc differences)

Like I said, I'm not crazy about the amount of drop after 22 yards but as a gap shooter I can figure out my gap in short order as long as I carry my rangefinder for a while.

[Buckeye Trad Hunter]

I'm positive that there is, but I wouldn't know what it would be.  Whenever the arrow weight topic comes up I always say think of it like this.  Take a golf ball a baseball and a bowling ball and throw them all overhand as hard as you can and see what happens.  I'm sure the golf ball bounces off the baseball makes a sizeable impact on the target and the bowling ball likely doesn't get there and if it does it bounces and rolls so much that all of the energy is spent before impact.

[Don Stokes]

My experience has been that 12 gpp is as heavy as I want to go. Past that point the trajectory suffers. However, if you're accustomed to it, the weight should be no problem for close range hunting.

[Rob DiStefano]

good topic.

for me, it's all about the arrow trajectory - what works best for me.  the arra will typically be between 9 and 12 gpp, but typically 11.  

too low an arra weight and usually the bow (and my bow hand) complains.  too high and the difference in trajectory 'tween 15 and 30 yards is too much to calculate all the time.

as always, there are lotsa other dependencies such as holding weight at full draw and form.

to me, that's all that matters with "diminishing returns", and not at all about penetration - if my arrow is built right and flies right, if the broadhead is sharp and if my aim is true, then penetration takes care of itself.

the year I shot a 160 pound doe at 35 yards with a 5/16 cedar with a Grizzly broadhead shot out of 67" 51 pounds @26" purple heart Zebra Super Grevy and watched the arrow fly over the hip beyond the deer, never to be seen again, was a wake up call for me.  I was reminded of that later in that year while searching for an arrow my wife shot through a deer with a 37 @ 26" recurve shot with one of those same 5/16 cedar arrows, never to be seen again.  Both of those deer went down in less than 50 yards and were shot from the ground.  Perhaps those setups will not blow through a shoulder bone of an elk, but deer ribs were no match for them.  I do like 10 or 11 grains per pound, not for penetration, but for how the bow feels, with heavier bows I simply use whatever cedar flies and that is most times about 9 grains per pound.

[S.C. Hunter]

I am sure you do reach a point where the returns diminish. I have never shot over 10 gpp with a avg of around 9-9.5 gpp. I have never had a problem from a 55-57# bow for deer or hogs. Never shot a elk so no personal experience. I do know a hunter in Fountain valley who has photo's at our local range of everything from deer, elk and hog that he shot. He said he always uses about 9-10 gpp.

[Doug in MN]

Originally posted by Rob DiStefano:

for me, it's all about the arrow trajectory - what works best for me.  the arra will typically be between 9 and 12 gpp, but typically 11.  

.

I try to get to 11 GPP, a little up or down is fine. The statement Rob made above rings true with me as well.

Arrow flight along with spooky sharp heads gets the job done.