Momentum V.S. Kinetic Energy

[BT]

Of the 4, I would opt for the phantom.
For optimum penetration I would go with the 2 blade stinger and this is why....
Mass.
The stinger has the least mass which would more than offset the minor K.E. difference.
(I'd wager....although I could be wrong.....have to measure it )
Take the total width and total cutting area (length) of the heads and add those two numbers together and then divide that by the K.E. for that arrow.
Do that for both heads and see which has the lowest number.
That lowest number will have the highest penetration K.E. factor.

[SPIKER]

I would say the Stinger. That head is crazy as far as penetration.

[BT]

Sept 11, 2009 0:51:51 GMT -5 BT said:

Of the 4, I would opt for the phantom.
For optimum penetration I would go with the 2 blade stinger and this is why....
Mass.
The stinger has the least mass which would more than offset the minor K.E. difference.
(I'd wager....although I could be wrong.....have to measure it )
Take the total width and total cutting area (length) of the heads and add those two numbers together and then divide that by the K.E. for that arrow.
Do that for both heads and see which has the lowest number.
That lowest number will have the highest penetration K.E. factor.

OR


you could find a friggin bucket!

;D

[stilllearning]

Yea I will explain more when I am down. There are reason for the lack of testing. My apologies. it will get done.

[BT]

[dinosaur]

Most interesting. A study of kinetic energy, which deals with motion only, as opposed to momentum, which deals with mass and velocity.

One cannot be truly pitted against the other. One person can only attempt to find the optimum for a particular range at a particular angle relative to the earth.

There are physical laws that apply as they always have. That's not really at question. Physics can easily explain why something didn't work. What it cannot explain is why and how humankind is capable of computing the exact angle and pressure necessary to evoke the perfect kill shot in a span of time that covers only a few seconds.

Man (this includes women) is the perfect computer. Somehow, both men and women have been able for hundreds of thousands of years to pick the perfect point, angle, and weight of their strike to impose the most damage on what was dinner.

Scientific analysis has been, at best, wanting to describe the basic ability of mankind to adapt to his or her surroundings and take what is needed for survival. Every time you go out into the woods to hunt, you are reprising a hunt that has taken place for millenia. Revel in it and understand that what you do is primeval. Guess, estimate, hunger, and take.

My freezer is always full. How's yours doing? I'm old but my aim is still good. I find that I can only draw about sixty pounds with ease. It's plenty. I always apologize to my kill for taking it. But i need the meat.

We can philosophize and extemporalize. We can devote major energies to physics and the study of momentum, mass, trajectory, and kinetic force based on mass. And what will we discover? We shall find so many disconnective possibilities as to boggle the mind. There are so many quadrillions of possibilities that it would seem better to simply go out and hunt. No two situations are alike. No hunt is like any other.

You're an archer. Enjoy it. Revel in it. It is man's, and there are no others like us on this planet. Godspeed.

[Doegirl]

Dinosaur, I love your signature

[stilllearning]

I need to get something off my chest.

I was all ready to help out BT this last year and test anything he wanted and then things changed for me and stress became my enemy. BT know and understands and has been very gracious in not pushing me to get things done. I feel bad that it did not get done for him and you folks but my life has changed in a way I did not see coming. I have a lot to still work out and will eventually allow my heart to heal as it has been broken. I am single now and finding it a little hard.
Sorry if you were expecting more from me but I just couldn't bring myself to get things done as far as the testing.

Again BT thanks for understanding and I hope I will be back on top of my game soon. But for now I will stay on the sidelines and watch things. I will post from time to time but ....... well who knows what will happen. As far as I see only God knows and he ain't telling me right now until I can handle some more.
See you around all.

[Konrad]

Dinosaur,

A true wordsmith, catching the essence of the hunt so well; however, those laws of physics can’t be ignored and you must admit they provide ample grist for the conversation mill?

I too have read a lot of discussion on this matter of folks trying to calculate the best killing combination and many are caught in the Kinetic Energy trap where speed is everything. Indeed, range estimation becomes less critical but merely striking the target is not sufficient when hunting. A K.E. calculation is the result of all of the moving energy possessed by the projectile (rotational, oscillation, vibration and forward travel combined). One can not draw any direct conclusions about any given arrow’s killing ability from KE calculations alone.

If this were true, the 7x57 Mauser round should stop a bull elephant charge every time.
Look at all the kinetic energy that 140 grain bullet possesses (2,200 ft. pounds)!
Sadly, this has been proven incorrect on many occasions. I know, I know Bell killed a thousand of elephant with this round but NOT stopping charges. They were well executed brain shots and he rarely took a questionable shot (he had seen too many of his buddies turned into red mud). He relied upon correct placement and penetration of a full metal jacket.

If we limit our discussion to archery projectiles only, it is my opinion that the “best” killing combination is the one where…
A: accuracy is paramount and
B: disruption of vital organs is only marginally second
By disruption of vital organs, I mean destroying the body’s ability to supply oxygen to the brain as quickly as possible.
Since we can not rely upon a mushrooming bullet producing the hydrostatic shock associated with high velocity rifle rounds affecting the central nervous system, we must attempt to disconnect as many oxygen supply routes as possible in the short period of time an arrow has to do its work.

I think many confuse the external ballistics of an arrow with the internal ballistics of the arrow. External ballistics relating to how the projectile performs while flying through the air and internal being what happens to the projectile during contact with the target.

While the arrow is passing through the target it may still be thought of as “flying”. Truly, it is a different media but it is media none the less. The arrow moves more slowly and looses its speed more rapidly than when passing through air but specifics can be measured and conclusions drawn from those measurements.

The time the arrow is moving within the target can be measured as a time pulse during which time the arrow expends its stored energy.
Many things contribute to the length of time an arrow can perform within the target including but not limited to:
Arrival speed of the shaft (impact velocity)
Diameter of the shaft (influences friction forces applied to the shaft by the target media i.e. larger surface are = more friction)
Style of the broadhead (two, three or four cutting edges, trocar, diamond, tanto or needle point)…a two edge uses less energy to cut than four
The mechanical advantage of the blade design (a steeper angle uses more energy during travel through the target)
Transitional differences from broadhead ferrule to shaft diameter (small to ferrule to large shaft offers more resistance)
Stiffness of the shaft as a whole (a stiffer shaft flexes less on impact allowing more forward progress…in my opinion, this is where carbon composite construction shines)
Weight of shaft (a heavy projectile possesses more mass and inertia retaining forward motion longer)
Weight distribution of completed arrow (Forward of Center distribution greatly reduces tail flexing and therefore allows more energy to be used in forward motion)

For any given bow the best killing arrow lives within the above.

It is my belief that “perfection” lies somewhere around .625 seconds time of flight to 50 yards combined with .625 seconds worth of penetration while delivering scalpel like cuts to everything along the way.

I know, I don’t ask for much!

[SPIKER]

My philosophy is that you can't kill it, if you can't hit it. That's the cornerstone of my belief that a faster arrow is always a better choice for me.

Up in a tree, distance is always a bit of a challenge , and the less I have to guess, the smoother the act of aiming, and releasing goes.

I hunt Whitetail, and don't believe there is a one that can stand up to my rig...I have always gotten passthroughs into the dirt with a fast, light set up, and will stick with what works.

Two holes are always better than one.