Mechanical Broadheads

[Ray]

I'm sorry your little program is interesting but does not  even come to replace the studies which have been compiled. They are just numbers and do not speak about many facets other than the ones which you feel compelled to focus on. You have a lot of time to catch up to Ashby. You have not compared two broadheads yet. I'll be waiting for your study. Patiently 

[Lowedog]

The important thing to remember is that this is about broadhead performance. Although you may find it a interesting for the sake of a small point that I was not necessarily trying to debate. The point  is not to prove a compound bow is a good performer when we are comparing and discussing broadheads and their ability to perform. If you are going to propose that people use mechanicals on large game then do some testing on elk and moose. Real testing. Not mathematics.

You actually have not proven what you wanted.

I really didn't want to prove anything.  Just that what someone else uses as long as they can use it proficiently is no business of mine.  

I am not proposing that WDFW make mechanicals legal.  I just am saying if they do it won't bother me if someone else wants to use them.  

There is a bunch of testing you can find all over the net for all kinds of BH's.  From shooting though steel barrels to actual deer bone inside of ballistic gelatin.  Bowsite has some pretty good tests they do on just about every BH out there.  

Anyway, to each there own.

-Lowedog

[Ray]

So is it ok for me to shoot blunts or field tips at deer or what? I can be proficient. Those mechanicals might as well be field tips when they fail to deploy.

[EastWaViking]

note to self: 

a 3 pack of Grim Reapers is probably not a good stocking stuffer idea for Ray this year. 

[Lowedog]

So is it ok for me to shoot blunts or field tips at deer or what? I can be proficient.

You do what you want Ray, or maybe you should ask the all knowing Ashby that question.

You seem to want to quote numbers and such from Ashby but when presented with actual numbers that prove your theory wrong you want to blow it off.  

You just keep going on about your closed minded ways...that is the only way that will be acceptable to you

-Lowedog

[Ray]

It's not my theory. You have only scratched the surface on the studies. You have only crunched numbers and have not comprehended many parts of his reports. I think you are a smart guy but your close mindedness has not permitted you to dive in and read them yourself and then come back with an intelligent response which adds up to good broadhead reporting. You can attack Ashby personally as "all knowing" or me for referring to his information but his reports are there and yours come from a calculator and program with no field studies and not having compared two broadheads.

[Lowedog]

It's not my theory. You have only scratched the surface on the studies. You have only crunched numbers and have not comprehended many parts of his reports. I think you are a smart guy but your close mindedness has not permitted you to dive in and read them yourself and then come back with an intelligent response which adds up to good broadhead reporting.

It's not your theory but it is the theory you are going to live by and refuse to be open to any other type of thinking. 

I did read his theory on what it takes to penetrate game.  Great theory but he also quotes numbers and his guideline numbers for heaving heavy arrows that takes very high poundage longbows to do so are easily equaled and surpassed with modern equipment and much lighter arrows and broadheads. 

Now what type of intelligent BH reporting have you put out?  That mechanicals are not worthy to hunt with?  That is your opinion, well I guess it's Dr. Ashby's but whatever, his opinion is yours I guess.  You would find many people across the country that would argue that point.  If you want to find testing that might give you an opposing view other than your own/Ashby's then you can easily find it by doing a search.  Ashby has already made up your mind for you though so why bother.

-Lowedog

[Ray]

It's not your theory but it is the theory you are going to live by and refuse to be open to any other type of thinking.

Completely untrue. I would love to read more reports. You just have not produced anything but hot air. Honestly would like to see more of these sort of reports from anyone. As long as they are well put together like his. I have said this before.

The rest is not worth responding to.

[Lowedog]

Google is a nice search engine...

[Ray]

I bet it is but as far as I can tell nobody has provided a comprehensive broadhead report which has spanned so many years and studied so many broadheads as well as by someone who is not getting paid to promote products. 

[tlbradford]

Lowedog...Your program is flawed in regards to arrow penetration.  At least from the numbers you have posted here.  From what it looks like, someone took a ballistic calculator used for cartridges and converted it to arrows.  Please email it to me when you get a chance or upload as an attachment to your post and I will play with it. 

I am going to try to break down physics in the easiest possible manner for everyone reading this.  (That may only be me, you, and Ray at this point)

Momentum = Mass*Velocity.  Momentum is what determines penetration.  For our arrow weight test Mass is a constant.  So what are the variables that can effect Velocity?  That is how you have to think about this problem.  Friction increases as the broadhead penetrates the target.  Friction will slow a smaller mass more quickly than a larger mass.  What increases friction?  The number of blades, the type of point, the cutting surface area, the drag of the arrow shaft, the type of material the shaft and head is made of.  What else will have an effect on the forward motion of the arrow?  Any mechanical process that is needed to open blades.  Try jumping straight up in the air as high as you can go.  You throw your arms straight up in the air to help keep your momentum in a straight line.  Now straight up in the air while throwing your arms out to the side.  Did you jump as high?

Ashby didn't come up with this stuff on his own in 1997.  The mathmatical theories behind his studies have been around for hundreds of years.  All he did was take physics and relate it to arrow penetration.

What are some of the advantages of mechanical broadheads?  One of them is they can offer better flight characteristics and stabilize the arrow more quickly.  This will keep the momentum of the arrow in a straight line and will give it better penetrating power than an arrow that wobbles.  Stable arrow flight is one of the top factors for penetration.

I don't need to present any scientific data to prove that a single fixed piece of steel has greater structural integrity than something with moving parts.  If your common sense can't figure that out, than it isn't worth trying to convince you otherwise.

In any type of hunting you are trying to inflict fatal damage to an animal.  With bullets that can be a transfer of energy that ruptures cells and damages organs due to the impact of a bullet.  In bowhunting, maximum penetration is king, since this will cut through the maximum amount of tissue.  Kinetic Energy should not be used to determine killing power when talking about bowhunting.

If you want to really delve into the math behind this, study this link.  http://en.wikipedia.org/wiki/Momentum  Pay particular attention to linear momentum.  Then study up on friction which will help you better understand what forces act upon an arrow in flight (air drag) and as an arrow enters into a target.  http://en.wikipedia.org/wiki/Friction

The only advantage to hunting with lighter arrows is a flatter trajectory and the amount of time spent in the air before it reaches an animal.  Period.  A heavier arrow, with all of factors being the same, will penetrate better out of a bow that shoots 300fps than a bow that shoots that same arrow at 290fps, regardless of the type of bow. 

I appreciate your openmindedness to all forms of bowhunting, but you are using a program that gives you bad information in regards to arrow penetration.

As far as testing studies.  Every "independant" study I have read has shown that mechanical broadheads fail at a higher rate than fixed.  I can find numerous studies that are backed by manufacturers that state otherwise but those aren't exactly unbiased.

[Ray]

Interesting. Well I just want to point out that once you determine momentum you also need to consider what the broadhead is comprised of, how it is designed, what the arrow is comprised of, arrow shape, arrow surface and overall design. Just the momentum numbers alone (which are very important) are not proof that one example will penetrate better than another. It is about the broadhead and the arrow and when I mentioned someone could choose a better broadhead and arrow combination to even the playing field somewhat it doesn't mean just weight. It means the actual products which comprise the arrow.

[EastWaViking]

the bottom line is this:  Mechanical broadheads are illegal in WA, and if your bow is tuned right, there is no need for them anyways. 

[Lowedog]

the bottom line is this:  Mechanical broadheads are illegal in WA, and if your bow is tuned right, there is no need for them anyways. 

True dat! 

I don't know how this got into such a big argument with Ray and maybe others thinking that I was a proponent of mechanicals because I am not.  I am neither for nor against them.  I simply was trying to state that arguments can and have been made that they can be very lethal on big game.  I never once said that they are in anyway better than a fixed of any sort.  The example numbers that I put out are just that. 

Any point that I was trying to make about heavy vs light is that a fast modern compound can shoot a lighter arrow and produce the same type of momentum and energy figures as a much slower traditional bow that is shooting a very heavy arrow. 

Its completely obvious that a faster bow shooting the same weight arrow BH combination will penetrate better than the slower bow.  That wasn't my point at all. 

I am in complete agreement that a fixed blade is stronger and tougher than a mechanical.  I just don't have the opinion that all mechanicals are garbage and have no place in the archery hunting world.


-Lowedog

[Lowedog]

Lowedog...Your program is flawed in regards to arrow penetration.  At least from the numbers you have posted here.  From what it looks like, someone took a ballistic calculator used for cartridges and converted it to arrows.  Please email it to me when you get a chance or upload as an attachment to your post and I will play with it. 

Just emailed that program to you.  I tested the program against the numbers that Dr. Ashby used for the 710 grain arrow shot into the bucket of sand example and the program gave the exact numbers. 

Mess around with it and see what you think.  It takes into consideration a bows IBO speed rating and calculates what you would get with variances from IBO in regards to draw length, draw weight and arrow weight.  I have tested it over a chrono with a couple of my bows and it has been spot on.

-Lowedog