How Important is Kinetic Energy in Bows?

[Smossy]

KE

[lghtnquik]

Not too bad do a little research on KE vs momentum and you'll be surprised. Don't get hung up on meaningless numbers the indians were killing 2000lb buffalo with 40lb recurves for hundreds of years.

[turkeyfeather]

Not too bad do a little research on KE vs momentum and you'll be surprised. Don't get hung up on meaningless numbers the indians were killing 2000lb buffalo with 40lb recurves for hundreds of years.

I was kinda thinking the same thing. It does seem that sometimes we all get a little to hung up on numbers. 

[bowpredator]

I read somewhere that it take something like 35-40 lbs of kinetic energy to kill your average deer, not sure on elk. My Bowtech D/350 is putting out almost 80 with the way I have it set up. But that's for elk hunting, my thinking is more is better.

[RadSav]

Numbers are important to me.

I thought you were suppose to be out killing some bear 

Think of the numbers in regards to arrow KE this way... If you could eliminate all friction from an arrow/broadhead how much KE would you need to shoot through a tree?  The answer would be less than one!

Unlike a bullet you are not trying to transfer energy to the target.  You want as much of the energy to stay in the arrow.  Shoot a few animals with your bow first before you start worrying about KE.  It won't take you long to realize that the amount of energy left in the arrow after it passes through your target makes little difference.  And that KE, like speed, is far more important to the sale of goods and to those who never shoot anything than it is to successful bowhunters.

[turkeyfeather]

Not too bad do a little research on KE vs momentum and you'll be surprised. Don't get hung up on meaningless numbers the indians were killing 2000lb buffalo with 40lb recurves for hundreds of years.

I was kinda thinking the same thing. It does seem that sometimes we all get a little to hung up on numbers. 

Numbers are important to me.

It's more important learning to be a good shot and a sneaky bas****.

[earlmarne]

i am no expert.
im broadhead tuning the old ladies bow today.at 45 lbs and 26 inch draw she is well below you in terms of KE.
in my mind proper and perfect arrow flight is more important.if i can get every last grain of that arrow behind a sharp blade without waisting too much of its energy in correcting flight i have complet faith that she will be getting pass throughs if she stays out of the shoulder.
i have piles of arrows laying around for my bow.from 575 grains down to 350 grains.i am generating just under 90 lbs of KE on release of my 420 grain arrow right now and it is overkill by a long shot.
my next bow will most likely be much lower poundage.
focus on tune and i believe you have nothing at all to worry about.but as said i am just a new guy to this whole sport

[RadSav]

I knew you would chime in.  Im only worried about KE because Im trying to build some good arrows that I can stand by for as long as possible and shoot anything I need to. With my bow I'm barely pushing 230fps, that kinda bothers me.

Where are you getting 230 fps?  When your bow left my place it was shooting just under 260.

[RadSav]

If I'm not confident with my gear, There's no way I can be confident with myself.

What is going to give you confidence in your equipment?  Is a high KE number going to do it for you?  If that's all you are worried about it's time to get an 80# PSE and Piledriver arrows.  And perhaps you need to start shooting a bow that is 2" too long in draw length for you 

Myself I think it's about time you shoot something besides targets.  A month from now you should have some meat in the freezer and your confidence should be plenty in your KE.

[SemperFidelis97]

Smossy you will be fine if you put as much mental energy into finding critters as you do breaking down how your bow works.  I have had the privilege of taking a few animals with my bow, and I have always been suprised by the devistation a properly placed arrow will do.  Simple truth is if you can put your arrow where it needs to go when you have the oppurtunity you will have no problem ethically killing any animal.

[RadSav]

Smossy you will be fine if you put as much mental energy into finding critters as you do breaking down how your bow works.  I have had the privilege of taking a few animals with my bow, and I have always been suprised by the devistation a properly placed arrow will do.  Simple truth is if you can put your arrow where it needs to go when you have the oppurtunity you will have no problem ethically killing any animal.

Well said SemperFidelis97 

[RadSav]

I knew you would chime in.  Im only worried about KE because Im trying to build some good arrows that I can stand by for as long as possible and shoot anything I need to. With my bow I'm barely pushing 230fps, that kinda bothers me.

Where are you getting 230 fps?  When your bow left my place it was shooting just under 260.

IBO is 295. With every fps calculator in existence, with my draw weight, length, arrow weight, and everything added to the strings. That's what I'm getting. like 228fps
62lb Draw Weight, 28" Draw, 28 3/4 arrow length, arrows weigh 398grains, D-loop, brass insert nocking point, string silencers. Approx 30grains

Did you change from the GoldTip XT 5575 spined arrows?  Did you add wraps?  I'm trying to figure out why they are 16 grains heavier than what I had here.  At that time they were 382 grains with about 11.3% FOC.  NOt sure what fps calculators you are finding in existence these days.  Mine says even at 398 grains you should be above 255 fps.

Velocity loss due to D-Loop, string Leaches and brass nock point is well over stated in the crapazines and on Archery lies and arguments website.

[RadSav]

lol @ I can barely afford to shoot targets, led alone anything that has a heartbeat. Id be doing more harm then good right now.

Are you smoking crack again!

[Austrian Hunter]

Smossy, confidence will come from the first kill.  I do understand what you saying but don't get hung up on these numbers.  All your practicing should give you plenty of confidence to put a well placed arrow behind the shoulder.  Just put some meet in the freezer and you wont worry about that again    Good luck to you!!!! 

[RadSav]

Are you smoking crack again!

Wtf?

    Oh goodness, You are entertaining and fun! 

If you can make it down here to work two days between Tuesday and Thursday I can help you out.  We can probably make it out to the range one afternoon and get a real fps on that bow too!  We can also go over Google Maps and I can give you details of where those poor little deer will be hanging out opening day. 

I think you just need to get an arrow bloody.  Everything will start to make sense again after that!

[Austrian Hunter]

I think you just need to get an arrow bloody.  Everything will start to make sense again after that!
[/quote]

  

[RadSav]

Hey, sorry if I hit a nerve.  Was just poking a bit of fun at ya being worked up about KE.  KE really is nothing more than a made up number to assist manufacturers in the sale of bigger, badder, faster and more expensive bows and arrows.  Makes very little difference on this continent.

I personally am thrilled with the way you have your bow set up.  Good arrows, good bow, great accessories...you should have all the confidence in the world with that.  You should also be pleased with yourself for doing such a good job getting it so well fitted and balanced.  I was very impressed when it was here.

However, if you can not seem to find confidence in what you have there I doubt an arrow change will make much of a difference.  In that case you would probably need to upgrade to a different bow.  You do have a bit of spine to work with using your existing arrows.  I think you could add another 12 to 15 fps before you needed to start looking at a stiffer spine. 

Both Lorraine and I have been eye balling those awesome boxes you have been making.  She wants one for her collection of small gems and I would like to get some custom arrow boxes and maybe a takedown recurve bow case.  I'm sure we could work up a trade if you feel the need to upgrade!  Might not be a Hoyt though

[mountainman]

Smossygirl, it is more important to have a truly sharp broadhead that you can put in the right place, then how hard it "hits" the animal. My friend Dwight Shuh shoots a relatively light poundage bow and relatively light arrow with light "kinetic" energy, but kills many large animals a year. Hunting skills, an accurate arrow, and knowing range limitations with your set-up go much farther in gaining that confidence then what the energy levels are! And if ever up in Wenatchee, stop by my shop to help out with any problems or concerns with your setup...

[270Shooter]

I am shooting a bow that ibos at 312 fps. Shooting 60lbs at a 28.5 inch draw with 27.75 inch gold tip kinetic xt arrows. I know it's not that fast. Doesn't have a ton of ke. But to 50 yards I know if I do my part and put that arrow right behind the shoulder it will zip right threw a bull elk. I think sharp blades are important too. And g5 strikers are just that!

[DoubleJ]

Smossy-

I shoot this:

Bear Legend
26" draw
48lbs draw
Beman ICS 500 w/ Savora 100gn broadheads weighing 340gn. total
233fps and 40lbs KE

Super sharp broadheads and it kills deer just fine.

[yajsab]

Smossy,

You are 28" in draw length and you are worried about KE.  I can tell you this.  You should focus on momentum and your target more than KE.  I am 2" DL short, and I used to care about speed (KE).  I have harvested many elks, but several years ago I started to pay more attention to momentum.  I up my total arrow weight from 370 to 430 grn.  Almost all my shots after that were passed through.  This is on elks.

[D-Rock425]

I had the joy of shooting a few arrows with you at the BBQ you shot just fine.  If you are shooting a hunt legal arrow in Washington you have enough KE to kill anything in the state.  Just worry about shooting straight and not the numbers you'll be just fine.  Its all about shot placement no if, and, buts about it.

[Song Dog]

Take one of them baseball pitching machines and set it at 120 mph  Stand in front of it and then you will know what Kinetic energy is

[dreamunelk]

Take one of them baseball pitching machines and set it at 120 mph  Stand in front of it and then you will know what Kinetic energy is

Ping pong ball or base ball?  Now momentum kicks in!

[coachcw]

look on the bright side at 255 fps your broad heads will fly great . the biggest peace of advice I'd give a new bow hunter is , while shooting at game don't hold too tight to the shoulder . there's plenty of kill spot further back and you don't want  to stick one in the shoulder. your arrow will get it done if placed well. Remember it's about hemorrhage !

[alwinearcher]

Smossy,
Here is a picture of my wife with a zebra she shot a couple years back.
She was shooting 44 pounds, 25" draw and a 400 grain arrow at a speed she wouldn't be ok with me posting
He ran 100 yards and tipped over dead... Its not about how much power is behind it! Make sure your broadheads are sharp and shot placement is good and they wont go far!

[RadSav]

Wow!  That's one of the more beautiful zebra I've seen.

[alwinearcher]

Wow!  That's one of the more beautiful zebra I've seen.

No, her name is Shannon

[huntnnw]

 

[RadSav]

I wasn't going to say nothing about someone else's wife.  

Though I am certain that animal looks one heck of a lot better in her pictures than it would have in mine.  Absolutely no question about that!

[alwinearcher]

I wasn't going to say nothing about someone else's wife.  

Though I am certain that animal looks one heck of a lot better in her pictures than it would have in mine.  Absolutely no question about that!

Yeah every animal she shoots seems to look better then every animal I do...
Woman!
 

[norsepeak]

I'm a big believer in high KE.  I mean, why not have the highest KE you can get?  If you are getting enough speed have manageble pins, then why not have the KE too.  I'm shooting my hunting arrows at + or - 305 fps, and they are heavy giving me very high KE.  So what does that mean?  Well, it means that if you happen to make a marginal shot, say into the shoulder of an elk, you are going to be more likely to get that elk then someone with less KE.  Is it super critacal for killing animals?  probably not.  It's like driving two identical cars, one with a v-6 and one with a v-8.  All of that being said, my wife's set-up doesn't produce near the KE that mine does, but she was able to harvest a nice buck last year.  The most important thing is going to be putting that arrow right where it needs to be regardless of the KE, the speed, color or any other variable.  Good luck..

[BOWHUNTER45]

I wasn't going to say nothing about someone else's wife.  

Though I am certain that animal looks one heck of a lot better in her pictures than it would have in mine.  Absolutely no question about that!

Yeah every animal she shoots seems to look better then every animal I do...
Woman!
 

that is one of the most colorful pictures I ever seen ...must be the bow and the back drop 

[alwinearcher]

I'm a big believer in high KE.  I mean, why not have the highest KE you can get?  If you are getting enough speed have manageble pins, then why not have the KE too.  I'm shooting my hunting arrows at + or - 305 fps, and they are heavy giving me very high KE.  So what does that mean?  Well, it means that if you happen to make a marginal shot, say into the shoulder of an elk, you are going to be more likely to get that elk then someone with less KE.  Is it super critacal for killing animals?  probably not.  It's like driving two identical cars, one with a v-6 and one with a v-8.  All of that being said, my wife's set-up doesn't produce near the KE that mine does, but she was able to harvest a nice buck last year.  The most important thing is going to be putting that arrow right where it needs to be regardless of the KE, the speed, color or any other variable.  Good luck..

I agree, but the problem I see with making to big of deal out of KE is then new archers end up out bowing themselves... To
Much weight and to much speed hurts form and accuracy greatly!

[Elk whack master]

Don't worry! I busted a does femur and still took out the heart with a 40lb recurve 24" draw125 gr muzzy when I was a teenager. Just keep shooting and learn where to put that arrow!

[RadSav]

.22 Short has about 65 fpe.  .22 Long Rifle has about 115 fpe.  Most archers shoot bow/arrow combinations closer to that of the .22 Short and not that bone crushing super deep penetrating master of destruction .22 Long Rifle!  Sort of makes that KE energy issue within archery set ups a little insignificant, doesn't it?  Especially when there is usually energy to spare as the arrow is leaving the target animal.

[turkeyfeather]

.22 Short has about 65 fpe.  .22 Long Rifle has about 115 fpe.  Most archers shoot bow/arrow combinations closer to that of the .22 Short and not that bone crushing super deep penetrating master of destruction .22 Long Rifle!  Sort of makes that KE energy issue within archery set ups a little insignificant, doesn't it?  Especially when there is usually energy to spare as the arrow is leaving the target animal.

I love you...





I mean, nice observation sir..


 

Whoa! Somebody has a serious man crush! 

[RadSav]

Whoa! Somebody has a serious man crush! 

6:30 is half way through happy hour isn't it    I think most of us have been there at that age 

[mountainman]

Haven't met either Rad or  mr. Smoss... But this does concern me.....but this IS Washington forum, so I guess, oh well??!!?

[mountainman]

Will have to meet this Rad! He sure has helped many, evident on these threads! We butted heads a couple times, probably because we both seem to have been in this industry about as long..guess I just aged us both! Lol! Maybe when we meet, it will be true love just like Smoss has! Lol! (Jokingly, obviously)

[mountainman]

Yes Smossy, banter is fun, but life is too short man, too short..

[Smossy]

Yes Smossy, banter is fun, but life is too short man, too short..

What does banter have anything to do with life being too short?

[mountainman]

To take friendly banter, back and forth, too seriously, as some do sometimes..