heard something about heavy up front ,200 is better than 125,etc,why,my arrows fly real nice,but anything for better groups,,,jeff
Check out the Ashby info on extreme FOC with regards to penetration. Bottom line, as long as your flight remains good, more weight up front ain't a bad thing.
All my arrows from the CE 150's to the CE 250 have at least 200 up front and most times 250. Heck my wife has little 26" falcons and she uses 250 with a 25# bow, and the Penetration she gets out of a 25# is sometime greater than a 45# with a 125 up front. If you had the option, would you want to hit them with a tooth pick, or a javalin. ..i know it's a gross exaggeration, but a few years ago i was into balistic's and penetration , and hands down the most efficient killer is the larger heavier projectile. Hope that helps. Like Kevin said, check the Ashby reports they are a great source of valuable knowledge.
P.
Yes....a 200 g. head can be better but there are a few things to consider.
For example....A 200 g. head on a 500 g. arrow will be better if your arrow is still tuned or close to tuned as a 500 g. arrow tuned with a 125 g. head.
The reason can be found in the displaced energy regarding FOC and it's effects on an arrow's penetrating capability.
Something to consider...I believe a 125 g. head on a perfectly tuned 500 g. arrow will out penetrate a poorly tuned 500 g. arrow with a 200 g. head.
Ray ;)
I agree with the last statment. Bottom line is, when shooting a reasonable set up.(45 to 55 pds)
A 100 gr. cut on contact head with a 2016 to 2018 arrow, will go thru an elk, no problems out to 25 yds. I know I've done it. I think people get to caught up in the weight of an arrow. My arrow set up is 475 gr. and it flys perfect. All this weight theory is interesting, but I say shoot what ever flys good.
Like the others have said, a perfectly tuned arrow with 200 grains (or more) up front will out-penetrate a perfectly tuned arrow with 125 grains.
We are talking about Newtonian Physics here....
As we have said, momentum in archery is a good thing. The formula (in metric)is p=mv (momentum = mass x velocity).
Following the principals of a balistic pendelum, kenetic energy is lost at impact in the creation of heat (frictin loss of hide and flesh, including the conversion of ke to sound, heat, etc. - so forget kinetic energy calculations altogether, and don't use it in our sport - period! The wheelie guys love to sell it because of how impressive the numbers can get, but it means nothing here) but as the laws of physics state that memnetum is conserved (geek note: this is true only at impact where momentum before impact = momentum after impact) so as velocity is decreased, the transfer of momentum is made to the object, and you get penetration.
Hence, more mass of arrow the more momentum, and more penetration.
Sorry, the engineer in me kicks in again....
:knothead:
Clear as mud, eh? This is what you get when I have a good coffee buzz going. Dang Starbucks! :coffee: :coffee:
Bob, Very well put.
P.
Bob,
Now that you have the momentum, why stop now? :eek: ;) :biglaugh:
Bill
oops, back to the question, yes, you will likely go to a heavier spined arrow shaft to play in the realm of e-foc.......
It isn't just increase your tip weight and shoot.
An advantage of a tapered carbon shaft that comes out of the box w/ built in forward weight is as such:
You have the luxury of choosing the broadhead you wish to use for hunting the game you seek. You then have the added luxury of building the arrow around this broadhead to a desired overall weight with the added weight being installed to the front end of the arrow. Having this weight added to the front end aids the arrows ability to straighten out quicker and tends to keep the arrow going straight ahead when meeting resistance. Think of a dart and its front weighted design. In addition, it will require less resistance of the flethcing at the rear of the arrow to straighten out the arrow in flight. You can then use a smaller profile fletch which will tend to allow your arrow to maintain more speed and momentum downrange.
Think of your question in reverse. If you shift the weight towards the rear, the arrow will tend to take longer to recover and will require more resistance from the fletching to steer straight. At some point, having too much rear weight will induce yaw as the back end of the arrow will attempt to pass the front end as it meets resistance. Think of a dart thrown backwards.
It is fairly simple to build an extreme FOC tapered carbon arrow with proper spine to shoot out of a stickbow. It requires more effort to build such an arrow of wood. The heavier the wood, the more weight needed towards the front making for an arrow that may be too heavy for most use. I do believe Ted Fry has made footed wood arrows with an extreme FOC using a smaller low profile fletch pattern that he invented for his selfbow. If memory serves me correctly, this is the pattern that Ted shared with all for free and 3Rivers took it from him and renamed it as being theirs.
later,
Daddy Bear
QuoteOriginally posted by BobW:
We are talking about Newtonian Physics here....
As we have said, momentum in archery is a good thing. The formula (in metric)is p=mv (momentum = mass x velocity).
Following the principals of a balistic pendelum, kenetic energy is lost at impact in the creation of heat (frictin loss of hide and flesh, including the conversion of ke to sound, heat, etc. - so forget kinetic energy calculations altogether, and don't use it in our sport - period! The wheelie guys love to sell it because of how impressive the numbers can get, but it means nothing here) but as the laws of physics state that memnetum is conserved (geek note: this is true only at impact where momentum before impact = momentum after impact) so as velocity is decreased, the transfer of momentum is made to the object, and you get penetration.
Hence, more mass of arrow the more momentum, and more penetration.
Sorry, the engineer in me kicks in again....
:knothead:
Clear as mud, eh? This is what you get when I have a good coffee buzz going. Dang Starbucks! :coffee: :coffee:
:biglaugh:
QuoteOriginally posted by whossbows:
heard something about heavy up front ,200 is better than 125,etc,why,my arrows fly real nice,but anything for better groups,,,jeff
Easier to find sticking straight up out the ground. :D
Steve
Daddy Bear:
Excellent job writing chapter II. :thumbsup:
i have some axis 500 shafts that have a 100grn brass insert up front and i use a 125grn head=225grn they fly purdy dam good out of my #43 robert painter bow.
thanks for the physics lesson,mine fly good,just wanted to see what every body thought about it,,interesting,mmmmmmmm
I just went cross eyed
That is the science behind it :readit: , and for what its worth, I don't shoot arrows with e-foc or broadheads with single bevels.... go figgure. :biglaugh: