Arrow Lethality
 

This is a long article but well worth the read. The first 2/3 breaks down physics into terms that most nonscientific types (me) can understand.

http://www.datakey.com.au/steve1/Momentum.pdf

RE: Arrow Lethality
 

I only got halfway through it but at a glance it looks like a lot of interesting information. I printed it out so I can sit and ponder all the details. Thanks

RE: Arrow Lethality
 

Air bags, baseballs, buckets of sand...

Baloney, just shoot the critters...

RE: Arrow Lethality
 

A bit more reading for those who care.Natal Study

More.

RE: Arrow Lethality
 

After reading cycllones post, I'm sitting here biting my tongue.... I want to say it soooo bad....

;)

RE: Arrow Lethality
 

Come on man. say it! Don,t short yourself the self gratification. You let all that ball up inside and we might see you on the news on top of a roof.

RE: Arrow Lethality
 

Thanks for posting this Landjaeger. Very interesting and informative information.

Its really strange but................in a much simpler way, I already knew this.

;) Seriously, if a person thinks about it deeply, its not hard to realize that the heavier object moving at a reasonable rate of speed can and will hit harder than a lighter faster object.

RE: Arrow Lethality
 

True, if a 98 pound dude smacks you upside the head at 25 mph and then a 220 pound dude does the same thing the results will be any thing but the same. Or a car hits you at 55 mph and then a train. Same thing applies to arrows.

RE: Arrow Lethality
 

Huh? What? Go ahead...If it's bad go ahead....I'm an umpire, I can take it....
Maybe I'll tell you why I feel that way.

RE: Arrow Lethality
 

I bet even umpires have their limits. [8D]

I likely know why you feel that way. You're probably like most these days.... shooting plenty of draw weight with a high performance bow and hunting not much other than deer. If you shoot a 65+ pound high performance compound, putting out at least 65 ft lbs of energy, do you realize that your bow is putting out as much or more energy than Fred Bear used to take an elephant? And why are you using that much power for puny little deer? Light arrows and, often, mechanical broadheads demand that much power, even for thin skinned, light boned critters. Unfortunately, sometimes even that much proves to be insufficient.

Start going down the scale with draw weight and bow performance, or up the scale on animal size and toughness, that airbag "I don't give a rip" bucket of sand doesn't fly. Instead of having baseballs bouncing around in your skull, you need KNOWLEDGE. You HAVE to know how to maximize the penetration potential you can get with the energy you have available, and choose the appropriate broadhead (type, size and width) to cause as much damage as possible while still driving deep enough to do the job. Not to mention a little allowance for some extra depth, just in case everything doesn't go exactly according to plan.

The same information you don't care to know would be crucial knowledge for someone else.

RE: Arrow Lethality
 

I Like your style Arthur...

My compound bow is set at 64lbs...Yeah, but I wanted it more, but at nearly 10yrs old it's bound to lose a few lbs...

My setup used to be light and fast, shot knitting needles ....bow was too noisy so I went back to my old style slow, heavy, silent and deadly. I shoot 2317's XX78's 27", (overdraw)..5" vanes, straight with slight offset. Zwickey Diamonds 2 blade, with insert adapter, net at 168gns...

So I guess I don't fit into your stereotype.

Amen on the knowledge...but, It's not that I don't care to have it, Heck, I even fall into this guy's "Nerd" category I guess. I'm a scientist by profession and understand all of his physics equations...

Condescending...as Websters describes it is why I don't care to read his jibberish...I find his attitude condescending...

Yes, it's all legit, sound physics perhaps even worthy of a good Mythbusters episode....

The paper sites no references or sources, no data, no numbers from actual experiments.

It doesn't have to mention the fact that longbows have been used for centuries and proved sufficient for their makers..Maybe it should have mentioned the Penobscot Indian tribes of Maine and the fact that they perhaps built the first "multilimbed compound" bows that they regularly harvested moose with.

It does have it merits though...It might be interesting to neophytes....but I'll be darned if I'm going to change my style for the likes of this paper...

RE: Arrow Lethality
 

Oh yeah, sharpness, I found nothing describing the relationship between sharpness and lethality...It might be there, I only skimmed it over for the second time.

RE: Arrow Lethality
 

I believe that the article that I linked to is a summarization of a study done in the mid to late 80's at the behest of the Natal Game Commission. As I understand it was fairly extensive. I've looked for the original report online but I can't find it. I think "Traditional Archery" magazine ran the study in several issues in 2000.
It's certainly not the easiest reading for everyone but the information is sound and worth sharing.

RE: Arrow Lethality
 

An interesting article, but not as "scientific" as it seems. Don't get me wrong, I am not a mathmatician or a scientist, just a natural sceptic. It seems that the author has a bias toward heavier, slower arrows for a variety of reasons, and the math is being used to justify that bias.

First, the author makes it know that he is seeking to validate anecdotal field evidence of penetration of various arrows through real animals. While not worthless, it is difficult to draw too many conclusions from this kind of evidence because it is not controlled and relies on reports of possibly biased individuals (ie. they might choose not to report evidence that does not support their bias).

Second, the author does not supply any data to support his conclusions. While he does make reference to an otherwise undiscribed database of penetration data, apparently this database consists entirely of the aforementioned possibly biased data. "Trust me" is not a valid scientific methodology.

Third, many of the conclusions that the author draws are essentially the same kinds of things that we have all heard and experienced anecdotally ourselves(ie. a bow shooting a heavier arrow is quieter, a tuned bow will shoot better that an untuned bow, a slick arrow finish will encouner less friction going through tissue than a rougher finish, and damage to a broadhead's blades will dramatically affect pentration). While this tends to make us feel that the discussion is valid, and I am not saying that it isn't, it doesn't really do anything to support the main discussion of the paper (which is arrow momentum and how it relates to penetration).

Fourth, some of the discussion, while technically correct, is nonetheless not particularly helpful. One big example is the discussion concerning the invalidity of using kinetic energy, rather than momentum, as a measure of an arrow's penetration potential. While the author acknowledges that momentum is a portion of kinetic energy, he fails to quantify that portion. In fact, momentum is such a large portion of the total kinetic energy, that using kinetic energy to measure the relative energy of arrows is, in fact, valid. While momentum is more tecnically correct, it is likely that it is relatively no more useful in practical terms.

Finally, and most significantly, while it may be true mathmatically that a heavier, slower moving arrow penetrates better relative to a lighter, faster arrow, knowing this general fact is not particularly useful in practical terms either. That is, the author does not tell us how much difference in penetration can be expected in what range of weights and speeds. For example, all other things being equal, if a 390 grain arrow traveling at 280 fps and an 700 grain arrow traveling at 150 fps both pass through a 150 pound deer at 20 yards, what practical difference does it make if the heavier arrow retained more momentum when it came out the other side?

The article does contain useful information and is well worth reading. I just think that, for me anyway, the conclusions were disappointingly general and not particularly useful. Bottom line is: if you are happy with the way your arrow/broadhead combination is actually working, there is no reason to change your equiptment. To the extent that this kind of article will keep bowhunters from getting caught up in the manufacturer hype over squeezing out a few more fps by buying this year's model bow, then it is a good thing. Sorry for the rant, but that's my story and I'm stickin to it.

RE: Arrow Lethality
 

Here is the full report. Finally found it. LOTS of reading and LOTS of details.

RE: Arrow Lethality
 

I wonder if the current state of the art in broadhead technology (and increased arrow velocity) would alter this much.

RE: Arrow Lethality
 

pretty interesting

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You have to admit that any supposed "scientific" report that has flamboyant adjectives within every other sentence has to be taken with a grain of salt. I do believe the article draws some realistic conclusions, but any PHD worth his salt writing a paper to support observed findings would lay off the descriptive and leading narrative and add some actual supporting data.

I believe the good Dr. Ed Ashby misrepresents himself as having a doctorate in physics when he clearly is using a phd in English to write such a supporting document for his clear personal feelings. Not saying he's wrong .. just saying he didn't clearly represent all the facts.