Ethical Arrow Weight
 

I tried a search on this topic with no results, so bear with me...

Using a very general assumption, I wouldsay most on here shoot bows with somewhere between 275 and 315 fps. At those speeds, what do you consider an ethical arrow weight?

Same question presented another way - when selecting shafts and broadheads, do you begin the process with a target minimum of kinetic energy in mind, say 85 or 95 ft. lbs. and so on?

RE: Ethical Arrow Weight
 

Crow,
I select my arrows and then I will add weight with different weight tubes tillI get the most KE my bow will produce. I have been doing it this way for so many years it just seems like second nature. I just recently did this and would up with 3gr tubes to get the best KE my set up will produce. However with today's newer bows this probably isn't all that necessary but I still like aheavier arrow for hunting. I go light and fastwith my 3-D set up's though.....

RE: Ethical Arrow Weight
 

Not sure I understand what arrow weight has to do with ethics...

If you are shooting an arrow heavy enough for your bow to handle without it blowing up on you...it is gonna be fine to shoot a deer with. Not to say you can't mess with some weights to maximize your setup for the best combo of speed and KE, but, when talking about deer...they are not hard to shoot thru. If in doubt, lean towards the heavier side. I never choose my setup with any KE in mind...the resulting KE is what it is and I know it will be fine. If/when I go to africa or after moose, then I will make sure my chosen setup is producing the needed KE. The 85 and 90 ft/lbs you mentioned is no where near target KE...those #'s are very high.

When it comes to broadheads, IMO, leaning towards the heavy side is always going to benefit you.A higher FOC is going to provide you a more stable arrow flight and thus, an easier time getting good broadhead flight.

RE: Ethical Arrow Weight
 

Ethical arrow weight? You've got to be kidding me. Whats next? Ethical arrow wrap colors? Theword ethicalgets used WAY too much IMO.:eek:

RE: Ethical Arrow Weight
 

Jeez, I didn't mean it like that.

What I was trying to get at was - is there a minimum arrow weight you try to obtain for your hunting arrows? That's all.

And Robin, I was basing my KE measurement on a calculation I made onan assumed shooting scenario.Assuming total arrow weight is 395 gr. and is moving at 315 fps. Using the calculator at http://www.bowhuntinginfo.com/Kinetic%20Energy%20Calculator.htmkinetic energy is roughly 87 ft. lbs.

RE: Ethical Arrow Weight
 

It would seem to me you need to replace the word "ethical" with "efficient".

RE: Ethical Arrow Weight
 

I will only buy "ethical" arrows that are made in a "green" fashion. Then I will buy carbon offsets to help in eliminating the waste made from building them.:D

RE: Ethical Arrow Weight
 

Crow,
To answer your question and not ridicule your wording, your bow manufacturer sets a minimum arrow weight to 5grains of arrow weight for every pound of draw weight ie. a 70# bow should not have a arrow weight of less than 350gr. That is the lightest arrow they recommend and also they will void warranty if you use anything lighter. As for KE the common denominator generally used is anything over 45#'s of KE will harvest most north american game. However, if you are using a large cutting dia. mechanical that number does not apply, you would need to be in the 60#+ range IMO, If you use a COC Bh then it would apply. Like I stated earlier and as Robin stated, I try to tweak mine to gain the best combination of speed and KE....Also as Robin stated a KE of 80+ is not very common but with some bows is achievable. Most of my set up's over the last10-12 years have produced 70#'s+/- of KE (which I feel is necessary with the BH I use)and that has proven to work well for ME and my set up.I hear a lot of guys on here talking of an animal running offwith an arrowstill in itand personally I have never had this happen, I have found all my arrows on the other side of the animal after passing completely through them. To some that may not be important but I put ahigh emphasis on thatwith my set up's. Which is why I try to get the best combination with my set up's every time.

RE: Ethical Arrow Weight
 

Texas,

Thank you for the straight-forward answer.Youransweris exactly thetype of guidanceI was looking for. This year I have been trying to better understand the technicalaspects of bow hunting and one arethat has been particularly foggy for me in the past has been kinetic energy.

RE: Ethical Arrow Weight
 

This is a good rule of thumb.....but High Country is warrantying their bows for a lot less (3#'s?). I'd still stick with 5 for a hunting set-up (my preference) and go UP from there....based on your arrow speed.

Do you have access to a local bowhsop? They should have a chrono you can shoot through and a digital scale (to measure the weight of your arrows). In the absence of a digital scale.....you can look up the various components that make up your arrow, online, and come up with a guesstimate on total arrow weight.

That's all you need. Arrow weight (total) and arrow speed to figure KE.

RE: Ethical Arrow Weight
 

[quote]ORIGINAL: GMMAT

Thanks GMMAT.

Yes, I have access to a bowshop. I shoot a BowTech Guardian with a 29" draw, set at 70#. Yesterday I had it chrono'd at 317 fps. I had the arrow weighed on a digital scale at 390 gr.

Then I wanted to know the KE of thatset upso I looked up a KE calculator. Using the one at this link: http://www.bowhuntinginfo.com/Kinetic%20Energy%20Calculator.htmkinetic energy was 87 ft. lbs. with that scenario.

RE: Ethical Arrow Weight
 

[quote]ORIGINAL: Crowkilla

Brother you should have no problems with that set up at all!!!!!

RE: Ethical Arrow Weight
 

That doesn't sound right. I'm not saying you're incorrect.....but it just doesn't sound right. Sounds awful fast for that setup.....maybe 20fps too fast. I could be mistaken, though.

RE: Ethical Arrow Weight
 

I think a better title would be
"Common Sense Arrow Weight";)

These lighter setups some have been shooting the past 3 to 4 years are going to start going "boom".

RE: Ethical Arrow Weight
 

Not saying your not right either, but I had a similar setup out of my Guardian(before I switched to 60# limbs). If my memory serves me correctly, I believe I was getting about 290fps, with a 390g arrow, 29"@70#.

RE: Ethical Arrow Weight
 

Yeah, I thought it was fast too. I shot it three times through the chrono to make sure. First shot was 319, second 317, third 318. Based on the consistency of the readings, I went with it.

RE: Ethical Arrow Weight
 

Like I said.....(and I own a guardian, too;))....it sounds about 20fps toofast. That's one HELLUVA discrepancy if the Chrono is "off" that much (and again....I'm just saying what gives the appearance, to me, of being "off").

RE: Ethical Arrow Weight
 

Yall got me nervous now. I'm gonnago to Bass Pro tonight (puke) and have them weigh the arrows and chrono the shotto see if there is a difference.

RE: Ethical Arrow Weight
 

I would like to shoot through that Chrono.

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Crow, you have nothing to be nervous about!!!! Even if the chrono was off 30fps that would leave you just under 70#'s of KE,that up is still plenty to harvest any north american game!!!!!;)

RE: Ethical Arrow Weight
 

Absolutely correct.;) If his chrono is off that much, though....I'd wonder about his scale![8D]

RE: Ethical Arrow Weight
 

dont forget momentum into the factor......

i'll take a heavier arrow moving slower than a faster, lighter arrow every day for hunting. it will carry its energy better

momentum=MASS+VELOCITY

a 350gr arrow doing 305 fps has a momentum of 106750 and a KE of 72.31

a 450gr arrow doing 260 fps has a momentum of 117000 and a KE of 67.56

thats roughly my bow for IBO setup vs what i really shoot....i loose some speed..and loose a few pounds of KE, but i gain a good bit of momentum...it will be harder to stop my arrow vs the lighter, faster IBO arrow.

i played with numbers for a while to find the point where i have the fastest arrow producing the most KE...then found arrows that fit the bill. (i like math and numbers) i found that any heavier just takes away speed but doesnt do much for KE...i found it to be a nice arrow weight for my setup...though heavier will add more momentum...

my point is KE isnt everything...though were talking deer that weigh less than 300lbs and if shot in the vitals, dont really have anything that is tough....hide, muscle and maybe ribs, which break and bend fairly easy...

RE: Ethical Arrow Weight
 

Explain this part to me, Mauser. I have a hard time following these "momentum" arguments....and I'd like to understand it better.

A heavy arrow is harder to stop than a light arrow moving at the same speed. A faster arrow is harder to stop than a heavier arrow moving at a slower speed. These are generalities.....butThe KE formula figures out which one is "better" for us. I'm not sure "momentum" is understood enough. I know I'd like to know more about it....and why it belongs in the same sentence with KE.

RE: Ethical Arrow Weight
 

I wasn't implying those numbers are not possible...just that they are not common or "starting points". Even if the chrono and scale are off in your case, you are more than adequate for most game. I would guess your bow to be more around the 275 mark...but that isn't something I even check on my own setups normally.

RE: Ethical Arrow Weight
 

I agree that momentum has it's place no doubt, but for ME I would have stopped in there somewhere in the middle of the two examples you posted,where the KE peaked and I would still have more than sufficient momentum!!!! When I am setting up arrows and adding weight I look for the point right before the KE falls, at this point I feeltheset up is at it's best performing point, a good balance of speed, Ke and momentum!!!! Like you said you can't focus on just one part of the equation!!! That's just my .02, I feel a good balance of all three is great hunting set up and it has worked very well for me for many years.

RE: Ethical Arrow Weight
 

Mauser, FWIW below is the formula to be used when mass is measured in Grains:





Momentum = Mass x Velocity
225218

This is expressed in slug-feet per second.

For example, my Bob Lee recurve shoots a 670 grain arrow at 175fps, momentum is .521 slug-feet per second.

RE: Ethical Arrow Weight
 

How many slug-feet to shoot mechaincals, Bob?:)

(sorry....I hate it when i do that;))

RE: Ethical Arrow Weight
 

Never tested them myself...

I not sure if anyone ever really has. I know that Dr. Ashby tested (not on deer though) some of them (mechanicals), but Ibelieve that his number one determinant of penetration is arrow and broadhead integrity (including components). I don't believe that any mechanical head past this. I believe his second is broadhead mechanical advantage which I don't believe mechanicals passed either. If you're interested on researching, I could show you where to look.

RE: Ethical Arrow Weight
 

I was actually just kidding;)

I only hunt deer with mechanicals....and the integrity and penetration is fine for them.

Interested in what materials he was testing on for penetration and integrity, though.....if it wasn't flesh, cartilage and inconsequnetially small diameter bones.

RE: Ethical Arrow Weight
 

Big game animals, African mostly, I think.

RE: Ethical Arrow Weight
 

tex, for those figures, that is right where it all fell together like you said...just a nice balance of it all before you start eating speen and not gaining hardly any KE...

Jeff, its hard to explain....but what would hit harder?....a mack truck fully loaded doing 50mph or a mazda miata doing 90 mph? (bad comparison size is a huge difference but use your imagination....i know you got one ;) :D) think about it though...the lighter miata is traveling faster, but will be easier to stop because of its lightness...a sturdy brick wall might stop it...while the same wall will be laughed at by the mack truck....like i said...hard to explain...with deer, the difference probably isnt going to mean a whole lot....i dont know...i dont have the time and years of expirience and actual testing other than figures and my imagination and some reading and research....could get me an extra inch of 2 of penetration on a BAD hit when i need it...who knows...i could probably show it better with bullets....you can really see the loss of energy at longer distances with lighter bullets opposed to heavier bullets...im going to do ALOT of research and toying around before i buy a new bow/arrows....i will likely go with a speed bow...and throw some true LOGS on as arrows...aughta knock em off their feet! lol...DEAD is DEAD....we know that. my line of thinking is in times of bad hit...contacting a bigger bone than ribs...you and i both know STUFF happens...shots go astray...extra penetration and power can never be a BAD thing...

bob, point me in the direction of the Dr. Ashby studies if you can...i thought i had them somewhere but cant find them and never did get around to reading them fully....

RE: Ethical Arrow Weight
 

But your comparison should be more in line with say a camry and a regal......or a mack truck and a Peterbilt. When the numbers get skewed too badly in one direction the information derived is useless....and the "test" flawed.

We're talking about deer, here....and pointy tipped arrows.:D

RE: Ethical Arrow Weight
 

PM'd.

RE: Ethical Arrow Weight
 

i know Jeff, i know....we can debate stuff like this till we all turn blue in the face and blood coming from our ears....in the end, we all know a 200lb deer isnt exzactly tough to bring down...different strokes for different folks....im also searching for a broadhead that is practically bullet proof...my muzzys will do for this season...after that im switching....do i need a head that is practically bullet proof? no...do i need to shoot a heavy arrow(not that mine are exactly heavy) no...but its my prefrence...i wanna find a nice balancing point between weight, speed, energy, cutting diameter etc...while still having a very tough arrow and broadhead...oh ya....2 dream animals to hunt are grizzly/brown bear and cape buffalo with a bow....dont ask why...i cant give much of a reason and dont have a death wish...just a country boy with a dream lol...

heres the Ashby studies...

http://tradgang.com/ashby/

maybe Bob has other ones he can post...its raining...i dont have class today...got minimal work to be doing...im gunna do some reading...

RE: Ethical Arrow Weight
 

Anything under 450 grains is unethical and illegal in most states. If you hunt with arrows any lighter than that - you're just an ignorant jerk. Flat-out.

RE: Ethical Arrow Weight
 

First good post from you in a long time:D

How heavy arrow are you shooting? From what I understand, two toothpicks have more spine than your arrows[8D]

RE: Ethical Arrow Weight
 

My arrows weigh between 55 and 85 pounds. It says so on the shaft.

RE: Ethical Arrow Weight
 

That my friend is FUNNY!!:D

RE: Ethical Arrow Weight
 

Jeff, if you got the time sometime, youd probably like reading the studies...

i read Momentum, KE, Energy and arrow penetration...not word for word, but a thourough skim and read most of it...puts it all into an understandable reading...

is it needed to setup a bow and arrow in ways that Dr. Ashby describes to hunt deer? i doubt it...but, one day, it might pay off...

found it VERY interesting that Dr. Ashby says....."Outcome studies show that lack of penetration is the number one cause of a hit being non-lethal" taken from the article...

RE: Ethical Arrow Weight
 

I'm so glad I don't get caught up with this bs---get a nice arrow, put a nice broadhead on it, shoot it accurately...kill the animal.