Which is better for hunting in your opinion?

[archerjustin]

I'm curious to see what everyone's take is on this. After all the discussion in my last thread "How much kinetic energy do you have", I have a question for everyone. I can shoot an arrow 300fps with 83.4 lbs of ke or an arrow 280fps with 84.6 lbs of ke from the same bow. I know what I will shoot, but what would you shoot?

[uptracker]

Honestly, for an average man, all you have to do is shoot a decent bow at about 40 pounds. You'll kill it and probably have a few pass throughs.

I'll be buying my girlfriend a bow soon and she can't quite shoot 40 lbs. yet, but she could kill a deer. My buddy (who is on here) shoots 50 lbs. and does quite well.

I know both of them shoot a heck of a lot less than 80 lbs. of KE. I don't worry about it honestly. I just shoot the correct arrow out of a 60 lb. SB and have never had a problem. When I was youger, I shot 45-50 lbs. and stilll had pass throughs.

Probably not what you're looking for, but you'll get those comments I'm sure.

[deerslayer#1]

the one that has the best arrow flight

[GVDocHoliday]

In the recent article of inside bowhunting magazine, they did the speed tests of all the new bows. Drenalin, Vectrix, and Guardian(drenaline was the fasted of all of them by the way) and they did multiple arrow weights at 29" 70lbs. The most efficient arrow weight that had the most KE was an arrow that came in at 6.1gpi. Everything heavier than that decreased in KE and everything lighter than that, though faster, lost KE. I myself found these charts very interesting even though they didn't make mention of that trend in the articles.

So for me, I'd use the arrow that weighs in at 6.1gpi, and that's my target weight for heading out west in September.

[archerjustin]

the one that has the best arrow flight

I can consistantly hit a softball sized group at 50 yards with either setup as I've tried both arrows. I "beefed up" my arrows for an elk hunt this past September, and after re-sighting in, I was just as accurate as before. I know either arrow will be more than enough in terms of speed and kinetic energy for anything on this continent, just curious as to everyones opinion. I'm going to switch back to my Gold Tip Pro Hunters which travel at about 300fps. For me 1 lb of kinetic energy doesn't mean much when it's up that high any way.

[TnRidge]

I would shoot the arrow that gives me the best arrow flight with fixed blades , regardless of the arrow speed .;)
KE doesn't mean squat if the arrow isn't flying true , because energy is squandered when the forces aren't driving directly behind the point .
Momentum is a bigger factor in downrange energy ,and a med. weight arrow will retain more downrange energy than a feather light shaft . It's no different than a bullet , just a different projectile .
Now before you flame me ,check the facts regarding momentum . Dr. fred Ashby wrote some great articles on the subject .

[TnRidge]

Here is an exerpt for Dr. Ashby's report .It is momentum that gives an object in motion the tendency to STAY in motion. The greater the contribution of the object’s mass is to the resultant momentum the harder it will be to stop the forward progression of a moving object. Anyone who has pushed a car in neutral and then tried to stop it will understand this. The more of a moving object’s momentum that is derived from its mass, the more TIME it takes to stop it with any given resistance force.

It is common for proponents of light and fast arrows to counter that the faster arrow will have traveled a greater distance through the tissues in the same time period than will the heavier, and slower, arrow. This would be valid were it not for the nature of resistance forces.

As the arrow’s velocity is increased the resistance does not increase equivalently. The resistance increases exponentially. The resistance of a medium to penetration is reliant on the square of the object’s velocity (assuming objects of a given coefficient of drag; i.e., using arrows with the same external profile, material and finish). In other words, if the arrow’s impact velocity doubles, the resistance increases by a factor of four. If the impact velocity quadruples, the resistance to penetration increases 16 times!

The effect of exponentially increasing resistance is easy to experience. Try holding a hand out the window of the car, while the car is going at a velocity of 30 miles per hour (which is only 44 feet per second), and feel the air’s resistance against your hand. The resistance is very slight. Now accelerate to 60 miles per hour (a mere 88 feet per second). The velocity has only gone up by a factor of two, but the air’s resistance to your hand passing through it is now four times greater.


Now imagine the effect on an arrow passing through tissues. Tissues are more solid than air. They have a greater density. Their resistance to an object’s passage is higher. Visualize the effect as an arrow’s velocity increases from 150 feet per second (a fairly typical velocity from a mid-draw weight traditional bow) to 300 feet per second (as from a top line compound bow).

Let us now assume an arrow weighing 700 grains for the slower bow (150 fps is easily achievable with that weight arrow and a ‘traditional’ bow) and a 390 grain arrow for the faster bow (the advertised velocity rating for one of the newest compound bows on the market, using that weight arrow). The slower arrow has 0.466 slug feet per second of disposable net force. The faster arrow has 0.519 slug feet per second.

Lets also assume these two arrows are of same materials, have equal physical external dimensions (easily achievable), and both have perfect flight characteristics. The tissue’s resistance increase is totally dependant upon the velocity of the arrow.

The lighter arrow has 10.22 percent more disposable net force (and 123.2 percent more kinetic energy) than the heavier arrow but, because of its higher velocity, it is met by four times the resistance to penetration. Which arrow will penetrate further in real tissues? Empirical evidence from the outcome studies provides an overwhelmingly definitive answer. Both the frequency and degree to which the heavier, slower, arrow out-penetrates the lighter one is of such a magnitude that it must be viewed as the norm.


ALL MOMENTUM IS NOT THE SAME

Given two arrows, identical in shaft and broadhead materials and profile, and having EQUAL momentum, but possessing UNEQUAL mass, the arrow deriving the greater portion of its momentum from its mass will penetrate better. The Laws of Physics requires this to be true, andALL of my field test data validates this to be the case.

To say this in another way, arrow momentum derived through increasing arrow mass results in a greater gain in penetration than does momentum gained by increasing an arrow’s velocity. This is true because the tissue’s resistance is increased by the square of the velocity.


Let’s look at two arrows of equal momentum, but unequal mass, both of which expend all their available net force in the tissues. If the momentum is equal between two arrows at impact, the one with the greater mass has to be traveling at a slower velocity. As shown above, the slower arrow will be met by a lower resistance force than the faster arrow.

With the momentum of the two arrows equal at impact, their disposable net force will be equal, but the resistance force will be greater upon the faster arrow. Because of the higher resistance force, the faster/lighter arrow will lose velocity more rapidly, and its momentum will diminish at a faster rate than that of the heavier arrow. It will stop in a shorter period of time, thus it will have a lower impulse of force than the heavier arrow.

To quantify the potential for penetration we must first quantify ALL the directional FORCES involved.

KINETIC ENERGY: When an object is in motion, it has kinetic energy. Kinetic energy is defined as the total energy of a body in motion. Kinetic energy is scalar, or non-directional, in nature - it is the TOTAL energy, of all types, in all directions. That is: kinetic energy has magnitude, but it does not have direction. (Note that kinetic energy is defined as ENERGY, not as FORCE.)

[BUCKWIZZARD]

The faster one!!!

[Swamp Monster]

In the recent article of inside bowhunting magazine, they did the speed tests of all the new bows. Drenalin, Vectrix, and Guardian(drenaline was the fasted of all of them by the way) and they did multiple arrow weights at 29" 70lbs. The most efficient arrow weight that had the most KE was an arrow that came in at 6.1gpi. Everything heavier than that decreased in KE and everything lighter than that, though faster, lost KE. I myself found these charts very interesting even though they didn't make mention of that trend in the articles.

So for me, I'd use the arrow that weighs in at 6.1gpi, and that's my target weight for heading out west in September.


Don't you mean 6.1grains per pound of draw instead of gpi? An arrow weight 6.1gpi is pretty darned light consideriing even most bare shafts today are above 8gpi.

[TnRidge]

I knew the FACTS regarding momentum and mass would fall of deaf ears .:dizzy:

Given two arrows, identical in shaft and broadhead materials and profile, and having EQUAL momentum, but possessing UNEQUAL mass, the arrow deriving the greater portion of its momentum from its mass will penetrate better. The Laws of Physics requires this to be true, andALL of my field test data validates this to be the case.

To say this in another way, arrow momentum derived through increasing arrow mass results in a greater gain in penetration than does momentum gained by increasing an arrow’s velocity. This is true because the tissue’s resistance is increased by the square of the velocity.

[skipper34]

And to think that we used to shoot recurves and cedar arrows and we still killed deer.

[GVDocHoliday]

Don't you mean 6.1grains per pound of draw instead of gpi? An arrow weight 6.1gpi is pretty darned light consideriing even most bare shafts today are above 8gpi.

Yes yes yes yes yes...thanks for catching my mistake. I mean 6.1grains per pound...not inch.

[archerjustin]

Wondered about that Doc. Thanks Swamp Monster.

[Kelly Johnson]

I knew the FACTS regarding momentum and mass would fall of deaf ears .

Those that would listen...already know Tn;)

I don't even get into the KE conversations anymore. Like Columbus tellin em the world is round:lol:

[BUCKWIZZARD]

Those that would listen...already know Tn;)

I don't even get into the KE conversations anymore. Like Columbus tellin em the world is round:lol: Because anyone that knows it dont make any difference, dont care. Say my bow is 59lbs and I shoot a 320 g arrow at 312 would it be better to shoot a 400 g arrow 270, NOT!!

[Michihunter]

I knew the FACTS regarding momentum and mass would fall of deaf ears .:dizzy:

Given two arrows, identical in shaft and broadhead materials and profile, and having EQUAL momentum, but possessing UNEQUAL mass, the arrow deriving the greater portion of its momentum from its mass will penetrate better. The Laws of Physics requires this to be true, andALL of my field test data validates this to be the case.

To say this in another way, arrow momentum derived through increasing arrow mass results in a greater gain in penetration than does momentum gained by increasing an arrow’s velocity. This is true because the tissue’s resistance is increased by the square of the velocity.


The key statement in your comments from Dr. Ashby was EQUAL MOMENTUM. However, if you use the same bow and increase the mass of the arrow, the MOMENTUM will no longer be equal. So falling on deaf ears is not a fair statement. The fact remains that you cannot maintain EQUAL momentum by going with heavier mass from the same setup because velocity (a key component to figuring momentum) will have decreased.

[TnRidge]

It is momentum that gives an object in motion the tendency to STAY in motion. The greater the contribution of the object’s mass is to the resultant momentum the harder it will be to stop the forward progression of a moving object

[deerslayer#1]

I knew the FACTS regarding momentum and mass would fall of deaf ears .:dizzy:

Given two arrows, identical in shaft and broadhead materials and profile, and having EQUAL momentum, but possessing UNEQUAL mass, the arrow deriving the greater portion of its momentum from its mass will penetrate better. The Laws of Physics requires this to be true, andALL of my field test data validates this to be the case.

To say this in another way, arrow momentum derived through increasing arrow mass results in a greater gain in penetration than does momentum gained by increasing an arrow’s velocity. This is true because the tissue’s resistance is increased by the square of the velocity.

Huh.........momentum and mass.......deaf ears. This article by the Dr. Ashby
has been floating around for some time, its old news. In fact it pops up everytime a debate pops up about broadheads or KE. Believe me, I work with momentum and mass, no need to explain it to me, or think it fell on deaf ears. The physics you speak of is basic and rather dull. When those deer start running around with body armor..........Then I will start thinking about KE. Until then, I'm thinking about good arrow flight, a sharp broadhead, and a good blood trail............ :coolgleam :coolgleam :coolgleam

[TnRidge]

If you have a problem with basics of mass and momentum ,then dispute it with your own facts instead of just calling it BS . So far you have not shown any supportive data suggesting that increasing the velocity of an arrow will increase penetration . Mr Ashby's reports are based on fact , not his opinion .

[Michihunter]

It is momentum that gives an object in motion the tendency to STAY in motion. The greater the contribution of the object’s mass is to the resultant momentum the harder it will be to stop the forward progression of a moving object


Once again TN, that's a no brainer. But MOMENTUM will NOT
remain the same if you add mass to an existing setup. Momentum will decrease with added weight due to a decrease in velocity. All parts of the equation are necessary. I think what people fail to understand is that Dr. Ashby was refferring to equal parts of the equation EXCEPT mass. So yes, if you use the same arrow but increase the weight and use a CONSTANT speed (meaning two different setups) the KE will definitely increase. But they would both have to fly at the same speed to confirm Dr. Ashby's contentions.

[screamin tightlines]

I have always believed in before anything eles. Almost anything can bring down your game with a well placed shot so i would go with the one that gives you a better pattern at your desired distance.

[FREEPOP]

TnRdige, stop making sense ;)

I think we need to make quads that are 1000, no 1200cc as 700 or 800 are just way too under powered :lol:

Hype, hype, hype, hype :chillin:

[archerjustin]

TnRdige, stop making sense ;)

I think we need to make quads that are 1000, no 1200cc as 700 or 800 are just way too under powered :lol:

Hype, hype, hype, hype :chillin:

So you are saying that all of our trucks should be 4 cylinders, and everyone should shoot a .243 for deer and a .410 for ducks. It's not hype it's performance! It's like saying a pair of Swarovski binos aren't any better than a pair of Bushnells. They might not be THAT MUCH better but they do give you a small advantage. A .243 will kill a deer but not as at the range a 7mm will. My point is that under 30 yards some of these discussions are nonsense but if you want to shoot a bow out to 50 - 55 yards these are valid points to consider. Better performance = less room for error. Personally, I would be confident with either of my setups for any game, but my questions do make for interesting threads!!

[BUCKWIZZARD]

When we shoot at the deer target why does my arrow go in just as far as everyone elses. Even those guys with 70 lb bows and heavier arrows, they just all go in the same. I beleive the difference between 70-85 lbs of ke is just that close that it dont matter. Its just an arrow smokin through a deer!!! The new faster bows are much better than slower ones, its not HYPE go try one dont just read and listen to people talk, try one!!!

[BUCKWIZZARD]

If you have a problem with basics of mass and momentum ,then dispute it with your own facts instead of just calling it BS . So far you have not shown any supportive data suggesting that increasing the velocity of an arrow will increase penetration . Mr Ashby's reports are based on fact , not his opinion . What we are saying is it doesnt matter. Any bow set up properly will kill deer from 40 lbs to 80lbs,any of them. Have you shot any new fast hunting bows? Increasing the velocity isnt gonna get the arrow through a deer any better but its just a better hunting weapon!!! :evil:

[deerslayer#1]

If you have a problem with basics of mass and momentum ,then dispute it with your own facts instead of just calling it BS . So far you have not shown any supportive data suggesting that increasing the velocity of an arrow will increase penetration . Mr Ashby's reports are based on fact , not his opinion .

I believe the report as fact. But........there are too many variables, that you cannot add or subtract into the equation. Let me give you an example that anyone can understand. I remember way back when you could use a bale of hay for a target with a hunting bow and a 450 grain arrow............Try it these days with a 300 grain arrow and you know you will be looking for arrows. Why..........because the SPEED produced helps carry the MOMENTUM. Just like a sharp broadhead helps the MOMENTUM poduced by the SPEED stay in place. Remember we are shooting arrows through deer, not arrows through bricks.

[FREEPOP]

Here's a neat little education about momentum (inertia)

http://www.glenbrook.k12.il.us/gbssci/phys/class/newtlaws/u2l1b.html

[TnRidge]

I here ya' Freepop ! I think I'd rather get hit by a fastball at 90 mph than a bowling ball at 15 mph .
:banghead3

If you get bored with the facts here , you can allways read this thread on speed and momentum .
http://www.archerytalk.com/vb/showthread.php?t=397616&highlight=speed

[BUCKWIZZARD]

I here ya' Freepop ! I think I'd rather get hit by a fastball at 90 mph than a bowling ball at 15 mph .
:banghead3

If you get bored with the facts here , you can allways read this thread on speed and momentum .
http://www.archerytalk.com/vb/showthread.php?t=397616&highlight=speed Im so glad that you said that!!! The arrow isnt going to hit any harder going 200 or 400fps, its going to go right on through!!!! in fact the one going 200 might not go through!!! A deer that gets shot by a bullet at 4000 lbs of energy, sometimes dont even flinch.

[TnRidge]

........until it strikes bone .:yikes:

[BUCKWIZZARD]

........until it strikes bone .:yikes: Still isnt enough energy to nock them over :yikes: we do understand about energy but a bow just dosent make enough to worry about.Get your bow shooting fast and go hunting, you will appreciate the advice!!!:yikes:

[skipper34]

Did anyone read my post?

[TnRidge]

Still isnt enough energy to nock them over :yikes: we do understand about energy but a bow just dosent make enough to worry about.Get your bow shooting fast and go hunting, you will appreciate the advice!!!:yikes:

:bash: My point being that you might need that extra mass if/when your arrow strikes bone such as a shoulder . Deer can duck at the sound of the shot , and sometimes your arrow doesn't allways strike where you are aiming . Therefore the extra weight and broadhead design could possibly make a difference in penetration .

One question . How long have you been bowhunting ? What was the first bow you have killed a deer with ?

[BUCKWIZZARD]

:bash: My point being that you might need that extra mass if/when your arrow strikes bone such as a shoulder . Deer can duck at the sound of the shot , and sometimes your arrow doesn't allways strike where you are aiming . Therefore the extra weight and broadhead design could possibly make a difference in penetration .

One question . How long have you been bowhunting ? What was the first bow you have killed a deer with ? Bow hunting 25 years and I cant remember the first bow. I have always said any bow will kill a deer. I have hit deer in the shoulder and seen them run off and not find them, but that was a long time ago. The last doe that I shot my arrow went through both shoulders at 20 yards.You dont really beleive a little heavier arrow is gonna make a difference do you.I do know that a heavier arrow has more ke but im not going to shoot a broom stick at them. I think their would be a big difference in a bow hitting with 40lbs of ke than 83 but not at 80 and 83. I do see deer jump the shot and thats one big reason I like to shot a fast arrow. I dont worry about hitting a shoulder I worry more about hitting them up high if they duck. I just remember seeing deer at 35 yards and wouldnt shoot, now i dont even want them close to me. We can argue forever about this, you like a heavy arrow and I like a fast arrow. If your sitting in a tree waiting for them to get really close im sure you will kill them , I just dont hunt that way all the time !!! THE END

[TnRidge]

I never said I shot a heavy arrow . Go back and read my other posts on this thread and the other . I'm shooting a carbon arrow @ 8.9 gpi with a 100 gr. BH .That's about the average weight for a carbon hunting arrow shot out of a 65lb bow .
I'm just trying to state the facts regarding momentum/ intertia and speed .;) There were some misleading statements based on the assumption that increasing arrow speed increases penetration .
I have shot bows @ 180fps and 275fps . It made no difference on my accuracy , and penetration when I hit them in the boiler room . A heavier arrow may help peneration on shots that strike bone . Guys are also assuming that a faster arrow is a more accurate arrow ,when the opposite may be true . A faster arrow is harder to control in flight ,especially with fixed blade heads or with a less than perfect bow tune .
I could go on and on , but the speed freeks allready have their minds made up .

[deerslayer#1]

60 lb draw 310 grain arrow 330 fps = 75 KE

70 lb daw 400 gr arrow 290 fps = 75 KE

I used the speeds from "MY" Bowtech Extreme VFT, and Bowtech allegiance. Both 30 in draw length

Less draw weight + less arrow weight = more speed(shoots flatter=better accuracy) and the same KE (also easier to pull back)

more draw weight + heavier arrow = slower and the same KE as less weight

(5 grains per pound) 70 lb draw 350 gr arrow 300 fps = 70 KE
60 lb draw 300 gr arrow 330 fps =85 KE

Now tell me SPEED doesn't come into play when it comes to KE !

Those speeds are very attainable by several of todays hunting bows.

Moral of the story, practice till your arms fall off, and use a sharp broadhead.

[Joe Archer]

Speed doesn't kill, accuracy kills! What many here have eluded to here is stability. A heavier, slower arrow with more KE will be more stable in flight. It will be less affected by wind plaining, less likely to deflect, and generally more forgiving.
Some here say that if we are shooting deer at 10 - 20 yards it really doesn’t matter. I say that the average hunter should NOT shoot at deer beyond 20 yards anyway. What bothers me is that hunters that believe because they can shoot over 300 fps that long range shots are no problem at all.
<----<<<

[wackmaster]

Which ever is the most accurate and consistant with the set up either is gonna do a pass through so speed isent all that of an issue but if the shooter and set up is better with the faster rig then I's go with that:coolgleam

[DTrain]

Yes yes yes yes yes...thanks for catching my mistake. I mean 6.1grains per pound...not inch.

So Doc, if I am shooting 55lbs, I should be looking for a finished arrow weight of right around 335 grains?

[GVDocHoliday]

So Doc, if I am shooting 55lbs, I should be looking for a finished arrow weight of right around 335 grains?


I would assume based on that published data that yes. I know it seems wierd, but I would say yes.

Try shooting a heavier weight arrow and a smaller weight arrow through a chrono and then calculate the KE. That's the only way to know.

[Pinefarm]

GVDoc, thanks for the info. I was looking at the Carbon Express Maxima's for a new hunting arrow. If I used your 6.1 gr per pound, it came out to 378grs total, with everything aded. So, I added up everything on my arrow, if I used the new CE's and it came out to exactly 378! Could I be that lucky? I guess I'll buy some and try them out! :) ;)

[DirtySteve]

You would drop from 69ft.lbs to 65ft.lbs of energy but your arrow flight would greatly improve with a fixed blade broadhead. There is a ton of research out there that says you shouldn't shoot fixed blades at 300 feet per second. Doesn't matter which broadhead you are shooting.

[Michihunter]

Steve- What research are you referring to in regards to the fixed blade at 300fps? I can show you a ton of REAL world research that defies that logic. A well tuned bow is very capable of shooting a quality fixed blade head in excess of 300fps. Guaranteed.;) ;)

[fairfax1]

This is just personal experience. No tables. No calculations.

I've been bowhunting for 40yrs. Bows with KE's of probably 38lbs to 72lbs. Many deer.

I've liked 58lbs of KE (at muzzle, so to speak) to get me an assured pass-thru at 20yds on a broadside adult and hitting the entry & exit rib using a 3blade Thunderhead type point. (There, is that enough qualifiers?)

But now, I'm starting to reach for a little more KE than 58. For one I am targetting older bigger animals so that certainly has a bit of influence, but also I am getting much higher in the tree than before. The shot angles are steeper.

I think now that to get that arrow to pass thru and stick (somewhat stick, not be buried to the fletching) in the ground on the opposite side of the animal I've got to go to perhaps 63 to 65lbs. Still will use a 475grn arrow/head combo but now using Muzzy 1" 4blade.

I did get complete pass thrus on 4 of my deer this year using 58 KE...but they weren't steep. The 5th was and it had to punch through the broad shoulder blade. It didn't pass through, and it left for an ugly difficult tracking night. Got the animal but I'm thinking 64lbs of KE would have put that shaft all the way...completely thru....that big doe.

Anyway that's the way I see it. You can...I can....kill 'em with much less KE. We have before.
But, I want the extra horsepower for the shot that strays a tad.

[bigbuckmiddaugh]

i always go with speed. :)
Hands down, especially on todays bows!

I always wanted (might someday) build a device that will measure the arrow hit downrange. Then i can use this to measure with different weight shafts and what kinda of different numbers were produced.

[wackmaster]

I shoot over 300 and I only use fixed heads;) I wouldent ever sacrifice accuracy for speed, Speed really isent that big of a deal its where it hits and go's through that madders life or death of a animal;) just my 2 cents:coolgleam

[WILDLIFECOWBOY]

Hey wackmaster you look fimiliar from your pic there do I know you?