What about when it runs into something solid? You tell me.

Fortunately, I haven't had to bust through that many bones in my hunting, but I have done it... even using wood arrows. I seriously doubt that the arrows I've used since switching to aluminum in 1979 (2216, 2219, 2419 and now, 2315) have flexed nearly as much as a wimply 2213 would on a bone hit. But then, I've never had a high speed camera handy when I've taken a shot either.

You must try to understand that a stiff spined arrow would flex less on a bone hit than a softer spine arrow. Since a lot of people have tried to use light, marginally spined (in the case of 3D, probably grossly underspined) aluminums for more speed rather than just going carbon, it generally seems that everyone is comparing carbon to 2213's in both penetration and durability, and that's REALLY comparing apples to grapes.

By the way, I never said an aluminum would give away a 'great deal' of energy in flexion. Does it give up any more energy by flexing than a light arrow gives up to wind resistance before it gets to the animal? Who knows...

Arthur,you have hit on one of the points I have tried to make in this discussion in the past.At what point does the stored energy start to get wasted.Is it a good idea to put an 800 gr arrow on a 40# bow with a 26" draw.I really think that would be a waste.Where is the line drawn.Really with your setup I wouldn't call a 600 gr arrow all that heavy but for me it is heavy.I really think the arrow manufacturer's have it pretty well set on the heavy end.You need to be carefull on the light end.You can get too light but at what pooint are we too heavy.At what point are we too light,I think the AMO has set it nicely with their minimum chart.




We all are starting to agree that carbon penetrates better than aluminum.So that really takes the notion that ke,momentum or even speed is better for penetration out of the mix.
It boils down to how well an arrow is built or how well balanced it is or what material it is made of.I know from testing that my Nitro Stinger at 360 gr penetrate better than a 450 gr aluminum of the same diameter.The aluminum has more ke and momentum but DOES NOT penetrate better.This says to me that the arrow determines penetration and not any number that we come up with on paper.Yes the numbers are good guide lines and if given 2 arrows that are identical in everything except weight then the heavy would win out but that is the only time you can go by the numbers,unless of course 1 is shot from a tuned bow and the other 1 is not tuned to the same bow.Then we tip one with a 2" broadhead with 4 blades and the other 1 with a 2 blade that is 1" in diameter.The smaller head will win but the numbers will be the same.


You can also take a 700 gr arrow and get the foc down to 5% and it going to stop in it's tracks when it hits bone,regardless of what the momentum or ke is.I did this on a piece of wood with a stinger filled with water and it stopped dead in it's tracks but jacking the foc up to 10% made a huge difference.You can get by with less foc if you have high ke levels but if you go too low you are stuck.If you have low ke,then foc becomes of greater importance.

The fletching is a huge part.Put a 5" extreme helical feather on an arrow and you have in affect put a parachute on the back of the arrow(to coin a phrase that Arthur once used).In affect reducing the amount of energy that will be used at the target.Use a 3" slightly offset fletching as I do and you have increased the downrange energy.


The variables are way to endless to put all the importance on a couple numbers,yes they are a good guideline but that is it,a guideline.I could go on and on but I think I have already.



Just one more thing for you Arthur.

I built Kinetic II's for both our bows using what you give on your bow.


My Kinetic II would weigh 465 gr and produce 60.9 ft/lb ke at the bow.At 30 yards I produce 55.5 ft/lb ke.243 fps at o yards and 232 fps atr 30 yards.


You would use the Kinetic II 300's weighing in at 555 gr.You would produce 60.8 ft/lb at the bow and 53.5 ft/lb ke at 30 yards.222 fps at the bow and 208 fps at 30 yards.

You lose 2 more ft/lb ke than I do.


I did use the same fletch length on both arrows but that would make even more of a change.The reason you lose more than I is due to the length of the arrows.Mine are 27" and your are 33".I believe I had your setup right but even if it is not exact you can see how much difference there is in 2 bows and how much little things like arrow length play into the penetration issue.


Very interesting. <img src=icon_smile_tongue.gif border=0 align=middle><img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_cool.gif border=0 align=middle><img src=icon_smile_wink.gif border=0 align=middle><img src=icon_smile_approve.gif border=0 align=middle>

Did anyone else notice the arrows weighing 239 gr different was only .800 of an inch.He also used the same 125 gr head.What would have happened if the foc would have remained constant?

I have tested a few arrows and found that all arrows have their sweet spot,in most I have tested it is 12%.I have some traditional carbons that did better at 18%.

Just more food for thought.

<BLOCKQUOTE id=quote<font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>
KE is fps x fps= ?
? x wt in grains = ?
? divided by 450,240 = KE

&quot;Pain is weakness leaving
the body&quot;
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

Thanks for the formula. I too couldn't remeber the constant value. Based on this info I have approximately 74# of KE with my current setup.

Mike

Thanks for the workup, TFOX. 2 ft lbs difference with round energy wheels vs your cams? Not bad. Not bad at all. Almost makes me wish I'd gone with Command Cams instead of Accuwheels so I could blow you away.<img src=icon_smile_big.gif border=0 align=middle>

Just for the record. My arguments have been about light vs heavy arrows. Seems it always devolves into a carbon vs aluminum thing, but that was not my intention. I do believe that a carbon arrow will probably penetrate better than an aluminum arrow <font color=red>of equivelant weight</font id=red>.

As for what point an arrow gets too heavy, you have to use a chronograph and figure the arrow's energy. At the point it begins to lose energy, that's obviously too heavy. Mechanically speaking. I believe the old rule of thumb says more to the subject than anything else. 'Use the heaviest arrow that will still give acceptable trajectory.'

Edited by - Arthur P on 08/21/2002 17:47:24

<BLOCKQUOTE id=quote<font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>

<BLOCKQUOTE id=quote><font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>Ted Nugent , shoots lighter arrows to gain some speed for shooting such low poundage in todays standards <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

Oh really, with low pundage and light arrows he must be getting some poor pnentration. Oh wait, maybe the speed is what makes the difference. But I thought heavy arrows penetrated better no matter what the speed. By the arguments made here heavy arrows should penetrate better than light ones regardless of the speed so why would he need to shoot faster?


<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

Reading comprehension<img src=icon_smile_question.gif border=0 align=middle>

Correct me if I'm wrong here , but is'nt this thread about kinetic energy making better penetration?
There are two factors that create kinetic energy , speed and weight. Ted Nugent is getting more kinetic energy by shooting a light carbon arrow at much faster speeds , along with a flatter trajectory. Do you know how the kinetic energy formula works? Who said heavy arrows penetrate better , no matter what the speed? I think your missing the point others were trying to make about heavy arrows.
If you had a 350gn arrow and a 500gn arrow that were both traveling at 300fps , which one would penetrate better? Go to bowjackson.com and play around with the kinetic energy calculator , and you'll see where there will be different scenarios where a slower heavy arrow will create more kinetic energy and vice versa. If you really want to see where a slower heavier arrow will penetrate better , start shooting traditional. You wont see many (if any) trad shooters with light carbon arrows. Both speed and weight have their place in archery , choose which you want , but dont say those that dont choose your way are wrong.

Bowfanatic,

Ke will always decrease on an arrow when the arrow gets lighter.The only way to change that is to increase the poundage or increase the draw length.Downrange ke will vary with the way an arrow is built or the diameter of the arrow.

I have heard that Ted Nugent uses heavy carbons so that is really is a moot point.

I really don't understand the infatuation with someone who acts like a total idiot everytime he gets in front of a camera.If you like him,fine,that is your perogative, but saying he is one of the best bowhunters around like silentassain did, makes my stomach churn.

TFOX , I agree with your opinion of Ted Nugent. However , the point I was trying to make to silentassassin was , he gains his kinetic energy by going with the speed , to make up for the low poundage he shoots. I believe he shoots carbon express , which is a lighter carbon arrow.
You also said &quot;kinetic energy will always decrease when the arrow gets lighter&quot; , that couldn't be further from the truth. Two key factors in kinetic energy are speed and momentum (weight).
I have messed around with so many different arrow combos , I could probably open up a used arrow shop. I have increased my kinetic energy several times by going with a lighter arrow and increasing my speed considerably. More often than not , I have switched from heavier alluminums to light carbons and the speed increase was enough to make the kinetic energy a wash.
And for the record , I'm not ready to jump on the wagon that says carbon penetrates better than alluminum , too many variables. Target testing with video cameras , measuring penetration into foam target , doesn't cut it for me , I need field test results (live game) and at this point , there is no hard evidence that even remotely suggests that carbon arrows penetrate game animals better than alluminum.

BTW Arthur , you would love the command cams , their great!

Bowfanatic,you are definately in the minority.Most anyone that has used carbon on game will attest to the penetrating avnantages.The ones that havn't had good results were most likely due to a poorly built arrow or poorly tuned bow.


I am going to disagree that you can gain ke at the bow by going to a lighter arrow.If the arrows are tuned at both weights and the poundage isn't changed(or draw length) then a light arrow will not gain enough fps to increase ke.It just isn't possible,unless there is a tune issue.Maybe fletching contact issues or something that is off on the bow.

TFOX is right. If you look at Mullaney's bow test reports, he always charts out arrow weight, speed, KE and efficiency for a lot of different arrow weights. I've followed his reports for years and in EVERY case, as arrow weight drops, speed increases, KE decreases and efficiency decreases. Lighter arrows are not as efficient at absorbing stored energy from the bow as heavier arrows are, they carry less of the bow's energy away as KE and leave that extra energy in the bow to come out as noise and vibration.

We never needed shock absorbing doohickeys stuck all over the bow until light arrows came along. Now they're building the things right into bows.

Edited by - Arthur P on 08/21/2002 23:11:47