I was sharing my observations with Dr. Ashby a few months ago and he pointed out the key to breaking the 30% barrier is not increasing point weight, but reducing tail weight.
The nock has the longest lever arm and you have the most to gain by reducing weight there. The QAD nock is a mere 4-4.5 grains. When I switched from a light 9.5gr nock I picked up 1-1.5% in FOC!!!! Just 5 grains on the tail did what I had add 50+ grains to the front to do without affecting spine or trajectory!
Get those arrows tuned to fly with low profile short feathers and a tiny nock and you will be amazed at the FOC increase!
BTW, the higher your current FOC the more you have to gain from lowering tail weight. It is not a linear relationship.
p.s. yes I believe the turbolator does work based on my personal trials.
You didn't state what type of arrow, material wise, you were shooting.
I have a feeling this only works in carbon arrows. It certainly doesn't work with aluminum arrows shot from low poundage bows (37#-42#) and long draw lengths of 30" or longer when dealing with a 32" BOP aluminum arrow.
It seems that EFOC became practical, almost necessary, with the advent of carbon. You never saw heavy heads back in the days when wood was the only choice.
Your suggestion is interesting. Do any of our TG sponsors carry the light weight nocks you mention? I suppose the opposite would bs true to adding weight on the rear with Lumenocks and the like...
Pick a spot you are exactly right. The QAD nocks are available from a lot of places, but I don't know of any sponsors on here, but I'd love to find one.
Night Wing, these nocks only fit 5/16" carbon arrows. The priciples are the same regardless of shaft material. Carbon's stiff ness if an enabler because today's bows have cut in shelfs. If you look at ancient primitive archery societies FOC of 30% up to 40% was not uncommon, but their bows were wide increasing the dynamic spine of the arrow.
So in a sense we are relearning what subsistence hunters knew long ago.
Which came first...cut to center so we could shoot lighter faster stiffer arrows with less FOC or did cut in shelfs lead us to need carbon arrows because of reduced dynamic soine caused by the shelf...either way it is a system. Bow and arrow have to be matched.
:rolleyes:
Chopx2,
I use Easton Super Nocks. It's basically an 11/32" nock and it weighs 13 grains. I'm also shooting 3, 5" parabolic feathers. The Super Nock is attached to my 421 grain 2212 Easton Eclipse X7 aluminum arrows cut to 32" BOP.
With a 75 grain point weight, I wanted to know what the FOC number is and it comes out to 9%. The trade off is in GPP (grains per pound) and this gives me a 10.02 GPP arrow when shot out of my 42# bow. With my 37# bow shooting the same 421 grain 2212, it comes out to a 11.37 GPP arrow.
There is no way a 5/16" nock can be fitted to a 22/64" (11/32") arrow. But for discusson's sake, lets say it could. And I'm even going to go smaller with a 1/4" nock with 3, 3" feathers further reducing tail end weight.
One of Easton's smallest nocks is a G nock and it weighs 7 grains. It's also a 1/4" nock in size. If it were possible to afix a nock this size to a 2212 aluminum arrow (and again it isn't possible), reducing the tail end weight from 13 grains to 7 grains from nock weight alone and also having 3, 3" feathers instead of 3, 5" feathers, would give me an FOC of 10.5%. The gain is just 1.5% and this is predicated on a 75 grain point weight. But again, if I reduce tail end weight, I have to reduce point weight to 65 grains to compensate for the loss of tail end weight because aluminum arrows are not as stiff as carbon arrows. This would reduce the FOC to (9.5%). There is no way anyone shooting an aluminum arrow; no matter what size in spine, no matter the point weight, no matter the length of the arrow, no matter the poundage of the bow, is going to give them a properly spined aluminum arrow with correct point weight, to give them an EFOC of 30%.
You're telling me the principles are the same regardless of arrow material, but I deal in "reality", not principles. When it comes to aluminum arrows, I'm sticking to my guns and I'm going to reiterate that no one shooting an aluminum arrow for bowhunting is going to have a 30% EFOC arrow. I've learned a lot of things shooting aluminum arrows during my 47 years of bowhunting. The things I've learned have come from hands on experience from experimenting with aluminum arrows shooting 2013s, 2113s, 1916s, 2016s, 2018s, 2114s, 2115s, 2212s, 2213s, 2215s and 2117s out of my low poundage bows with my 30" draw length shooting 32" BOP arrows.
If you want to refute my statement, make a poll on Trad Gang for aluminum arrow shooters and see if anyone is shooting an aluminum arrow with a 30% EFOC. If you take me up on my offer to make a poll, I think you'll be hard pressed to find "one" person.
In closing, EFOC is the exclusive realm of carbon arrows, not aluminum arrows. Although I don't shoot wood arrows, I have a feeling anyone shooting wood arrows doesn't have a 30% EFOC arrow either.
Chop - you have some interesting ideas. But, I think I'll pass. I've attempted a number of tests to demonstrate to myself that increasing FOC increases penetration. I have been unable to produce any correlation.
Plus, I can't seem to wrap my head around the idea of disrupting the air flow over a wing. I suppose that would work as a brake. But, I don't really need a braking effect that I know of.
Thanks anyway.
Hey, Chop
Thanks for sharing thats a great Idea.
I think the basic principles of EFOC applies to any type of arrow, its just a lot easier with carbons.
Gilbert
Nightwing, you're correct. This whole issue of "hign FOC," "EFOC," and now "Ultra-EFOC" only came into existance with carbon arrows because of their increased stiffness versus weight.
With aluminum, as you become more and more stiff, the weight of the entire arrow increases. One gets to a maximum of about 17% to 19%. Some have said a little higher. Fine. But that's about the highest you will get and still have a tuned arrow.
On the other hand, Chop may have a point with bows that don't have shelves allowing the earlier archers to have higher FOC and still be tuned. I'm not sure where that limit was/is.
But, frankly, I'm not much interested because nobody can demonstrate the effectiveness of higher FOC.
Ashby rightly says all his work is not scientific. That's fine. That just means he only has an opinion. That's okay too. But, it means his opinion is not anymore supported by evidence than anyone else's.
So, if I were you, I wouldn't get too worked up on the subject and just continue shooting the arrows that work for you.
Using short, low profile feathers on hunting arrows is a BAD, BAD idea, no matter what your FOC. Please don't encourage such behavior.
Gee, maybe those "old guys" that were shooting tapered wood about 70 years or so ago knew a little more about whats what than they were letting on. I can testify that a 750 gr tapered maple has no penatration problem even when tipped with a big ol'snuffer and shot out of a slow hill bow............
Carbons are awesome for point loading, but woodies will indeed point load well also. I haven't tried to take them as far as carbons yet, mostly because the shafting is usually heavier. Aluminum's don't seem to like it at all.
Why can't a 5/16" nock or even smaller go on an 11/32" shaft ?
ChuckC
The highest FOC percentage I've ever had shooting a very heavy 637 grain 2117 aluminum arrow, with a 235 grain point weight, out of my 42# bow was 17%. The only way I could achieve this high FOC percentage was by lowering the brace height to give me a longer power stroke.
This is why I know if anyone is shooting an aluminum arrow, EFOC and ultra EFOC isn't possible.
QuoteOriginally posted by Night Wing:
You didn't state what type of arrow, material wise, you were shooting.
I have a feeling this only works in carbon arrows. It certainly doesn't work with aluminum arrows shot from low poundage bows (37#-42#) and long draw lengths of 30" or longer when dealing with a 32" BOP aluminum arrow.
Yep and you lose a lot more options than just efoc with a long draw, 31" draw and 32" arrow here. in my case draw lengh dictates what i will end up with and the options are few. Im not complaining i like my draw i just cant play with things like the rest of you guys. So i just get her flying stright and true and injoy the flight of my so so foc arrow. But i do wish i could play, it is fun to tinker.
"Ashby rightly says all his work is not scientific. That's fine. That just means he only has an opinion. That's okay too. But, it means his opinion is not anymore supported by evidence than anyone else's"
I strongly disagree with your statement. Dr. Ashby has conducted some pretty extensive studies looking at penetration on dead critters and the effect that FOC plays. This is not someone's random opinion...it is one based on a lot of field studies conducted in a scientific manner and being as objective as possible. To say that his opinion has no more basis or support than those who disagree is laughable. You don't have to be one sharp broadhead to recognize this. Where are the studies to refute his observations? Some guy shooting three arrows into a hay bale in his back yard? When Dr. Ashby says his studies are not scientific his words get deliberately twisted by his nay-sayers. He is simply acknowledging that shooting a dead animal under field conditions is a bit different than some type of lab experiment where a uniform material is shot under better-controlled conditions such as a bow held in a mechanical device with a triggered mechanical release. While not perfect, Dr. Ashby's results definitely show clear trends regarding how different parameters affect penetration. Those who feel threatened by his work may choose to ignore his reports. Many of us have an open minds and are willing to listen to ideas of building a better performing hunting arrow.
After reading this,it dawned on me I have some 2016 and 2018 aluminums tuned to a few of my bows.I had never checked the FOC.The 2016 has a 100 gr insert and 145 gr point.FOC is 19%,total weight,573 grs.The 2018 has a 90-something adapter and 175 gr point and FOC is also 19% and total weight 650 grs.I hadn't been interested in FOC when building these,just got them tuned.I am surprised it was that high.For sure,19 % is all I could squeak out of aluminums.I can't cut 1/8" off.Sounds like you guys were right on the money.
WTPOPS, Lots of insight there,Jim G
When Dr. Ashby says his work is not scientific, I believe he means it wouldn't pass peer review of other scientists for publication. Standards are very high for such endeavors, and as a former research scientist myself, I understand. It doesn't mean his work is without merit, it just means that it's unlikely that it could be replicated by others, or be accepted for publication in a scientific journal. Who else has the access he has to the testing media, and the archery skill to conduct the tests?
Whole animals are not a good test medium because of the high variability in the density of the parts the arrow passes through. To pass peer review scrutiny, the sample sizes would have to be enormously large, much larger than anyone would be willing to do. His work is fascinating, and there is much information to be gleaned from it, but it's still not "scientific" in the world of research scientists. It could only be considered anecdotal as best in that world.
JimB & Night Wing,
If you're going to chase EFOC with aluminums, you'd want to start off with a larger diameter, thinner walled shaft. Using a shaft with a wall thickness of .016, .017, or .018 would be counter productive to increasing FOC.
Don Stokes writes: "When Dr. Ashby says his studies are not scientific his words get deliberately twisted by his nay-sayers."
No, sir. Nothing deliberate. At least not here.
Ashby's work is not scientific because he hasn't produced enough date for his work to be reproduced by anyone. Further, I think that his work is lacking because he does not shoot into a medium which would allow him to create a statistically significant correlation between FOC and penetration. Fact is, with all his volumnes of writing, he never makes the attempt (at least all that I've read... and, please excuse me for reading a lot of his stuff, but not all).
Oh, yes. I have tried to see if there's a significant difference. I cannot do so. Anyone else is welcome to come up with a testing method and present their results. I don't know about others, but, I'm more than open to that.
If there is no statistically significant correlation between FOC and penetration, then what Ashby writes is merely opinion. That he is verbose, means not much. That he has shot a bunch of arrows, matters little (Heck, I've shot a bunch of arrows, and you wouldn't want to lable my posts "scientific").
Here's a real good opinion for Trad shooters who are in doubt: Don't take Ashby's word or anyone else's. Figure it out for yourself.
Sorry.
I attributed a quote to Don Stokes that should have been attributed to JohnV.
My appoligies.
Don's post is correct when he talks about the problem with the medium. Therefore, to find out the answer to the very narrow question "which arrow with which FOC has what penetration, one needs to design a test to determine that. Such a test is not too difficult. Instead, Ashby reports "average" results which have no meaning without the standard deviation. I believe he does so for the purpose of adding clarity to his findings that his testing did not determine.
That, my friend, is not science.
Again, Don, I appoligize for the incorrect attribution.
Bob
EFOC... It's a skinny carbon thing...
Nightwing, I am not knocking the aluminums at all, but my 42# whip has blown through 3 deer with lil epic 600's and 200 grain heads... also stabilizes with lil 3 in parabolic feathers... This was my Turkey bow that I used through a shoulder problem and I now shoot a 57# bow so i am not too worried about till my son get's up to 40# hunting weight...
As for Dr Ashby's research and Data.. may not be scientific with a standardized test medium in a labratory confines... But I'll take field data over scientific data everytime....
Scientific data is usually sponsored to achieve a desired result for those footing the bill... The Golden Rule in marketing- he who has the gold makes the rules... Just watch infomercials to get what i mean...
Being a military man in my youth, my LT usually had a textbook scientific approach to a problem that usually didn't go as planned, but us Sergeants' had a field expedient solution that just worked... wasn't scientific, but it was proven...
I am surprised as all this started as was someone sharing another way to do the same thing that most folks are doin... :dunno:
OK, I deliberately put "for Ultra FOC tinkerers" because I wanted to avoid debate on it's value.
The post was intended ONLY for those who believe in it or are testing it out for themselves.
For you non EFOC-believers, please continue to shoot what you shoot THERE IS NOTHING "WRONG" WITH YOUR APPRAOCH. I never said you were wrong and I really would appreciate it if you showed those who like shooting EFOC the same courtesy and not post and turn this into a debate.
As for my statement that the same priciples apply regardless of material is true as what we are talking about is physics. I DID NOT SAY you can achieve the EXACT same results with all materials. I also pointed out that reducing nock weight has a NON-LINEAR relationship to FOC. It isn't until you get close to 30% that you can see such dramatic changes in FOC though a few grain change.
Slasher,
This thread started out as an EFOC topic based on principles. Chop stated by shaving down the tail end weight, it was possible to get "any" arrow regardless of material (carbon, aluminum or wood) and turn the arrow into a high EFOC arrow.
I know for a fact there isn't any way for an aluminum arrow to have an EFOC or ultra EFOC of 30% because of the characteristics of aluminum. I've shot aluminum arrows for 47 years from light, moderately heavy, heavy and very heavy aluminum arrows and the highest FOC I've been able to attain is 17%.
Go back and look at the very first post Chop made to start this topic. It had nothing to do with arrow penetration concerning EFOC. For some reason, people started to inject the penetration of an EFOC arrow into this thread and this isn't what Chop stated in his first post.
On a sidenote, I know what a 42# bow can do since I own one which you can see in my signature. When taking game with my 42# and 37# bows and aluminum arrows, I rely on a GPP (grains per pound) arrow since I can never have an aluminum arrow with a high EFOC or ultra EFOC percentage.
Thanks for the correction, Bobaru.
With my wood arrows and relatively heavy points (160-190 g.) I achieve FOC of around 17% with arrow weights in the 600 g. range. There's no way I could ever achieve much more, and I don't believe it's necessary, or even important, anyhow. The fact is, as long as your arrow is heavier on the front half than it is on the back half, it will perform effectively on game if it's properly tuned and your broadheads are truly sharp. Dr. Ashby's work is most applicable to very heavy bows and very large, tough game. Most of us will never hunt Cape buffalo, and for North American game, ordinary hunting arrows with positive FOC are just fine.
Tinkering is fine, too. :) I just hope that folks don't get the idea that EFOC is necessary to get acceptable performance on the majority of game animals we will hunt. Confidence in your setup and straight flying arrows are more important than FOC statistics. It's scary to me to think that someone would go to too-small fletching to try to gain another percentage of FOC at the expense of the game we hunt. Fletching serves a very important function in stabilizing the arrow under less-than-perfect conditions.
QuoteOriginally posted by chopx2:
...Get those arrows tuned to fly with low profile short feathers...
Not an expert. But,
I had a little trouble shooting big 'ol 3 blade Snuffers using low profile, short feathers. They flew great UNTIL they touched something anything and if it was a glancing touch that arrow became, well, lets just say less than predictable. Tuned great bareshaft etc but that big broadhead really changed the equation by its very nature.
Something to be aware of. I had o go back to longer fletching to regain predictability under real hunting conditions.
Joshua
Joshua, that's my point exactly.
Nightwing wrote: "For some reason, people started to inject the penetration of an EFOC arrow into this thread and this isn't what Chop stated in his first post."
Not sure, but I could be the guilty party here. Chop is right that he was merely trying to relate that he found a way to increase FOC through lighter weight nocks, and didn't really want all the rest of the discussion. In a way, I don't blame him.
Still, Chop did justify EFOC based on when he believes people did in the past, before modern recurves. And, in the end, one must have a reason to work at increasing FOC. If not penetration, what? I'm not aware.
It seems most people walk away from the issue by saying "well, I don't hunt Cape Buffalo." While this is true, if I did hunt any truly dangerous game, I certain of one thing: I would conduct my own extensive tests to determine if EFOC was of value. Personally, I think Ashby is successful with Cape Buffalo because he is shooting bows with a high draw weight, yet I see people (not on this thread) using Ashby's opinions to justify decreasing their draw weight on North American game animals.
Bob
Bobaru,
Dr Ashby also shot asiatic buffalo with a much lower poundage longbow and high EFOC arrows and achieved dramatic results.
You're arguing about the inefficacy of something which you also admit you haven't read completely? Hmmm.
The one truth in all of these discussions is this-without proper shooting technique, properly tuned bows, and properly sharpened broadheads, all of this discussion is meaningless.
It also seems to me there's a majority of people coming to this website wishing to shoot very low poundage bows and still achieve a quick kill on game.
The lower your bow poundage, the more direct benefit may be obtained through the use of EFOC arrows. A 37# bow shooting a 385 grain arrow will NOT penetrate as well as a 37# bow shooting a 475 grain arrow- tuning and broadhead sharpness equal.
You can run thousands of test shots through ballistic gel all you wish to satisfy your penchant for scientific results- but they'll NOT prove a thing about penetration on something that is a 'mixed media' - like an animal.
I've had the benefit of keeping data on thousands of whitetail kills and several hundred hogs- and now have firsthand seen a bunch of hogs killed by a wide spectrum of tradgangers.
Less than five of the hogs killed by Tradgangers over the last three years have had a complete pass- through kill.
It's my belief, based on careful study of the Ashby reports, that many of the non-pass through shots could have been more effective had the archers shot heavier arrow/broadhead combinations.
Forgive me for being non-scientific, but isn't a heavy-poundage bow shooting an immensely heavy shaft sort of the same thing as a light bow shooting a light-weight bow shooting a relatively equally heavier arrow?
Shooting the Stickbow Page 153, "While it's been shown that for any given bow a heavier arrow will not necessarly penetrate further into game (and so be more lethal) than a lighter arrow, many bowhunters hold on to the theory that it does, therfore wooden arrows remain a viable industry in today's archery market."
Just for thought.
I do like the short feather idea. Once you get all the tip weight pointed in the right direction, the other end doesn't need much steering.
Bowmania
Go far enough in that direction and you end up with a bullet. I believe I'll stick with archery, and a minimum of three 5" feathers. I want my arrow to be corrected by the fletching if I make a less-than-perfect shot at an animal.
Ray Hammond wrote: "The lower your bow poundage, the more direct benefit may be obtained through the use of EFOC arrows. A 37# bow shooting a 385 grain arrow will NOT penetrate as well as a 37# bow shooting a 475 grain arrow- tuning and broadhead sharpness equal."
Please demonstrate that for me with results that are statically signifant to the 95% confidence level.
All the tests I've done in my basement support a different conclusion. I see others doing tests into ballistic gel that obtain other conclusions. I see others doing tests into phone books that obtain other conclusions.
The tests I've done demonstarte that I cannot come up with a significant difference. The videos I've seen into both ballistic gel and phone books support the idea there's probably no statistical difference (he gave the edge to the lower FOC while I would suggest no results - and no statistical tests being run).
All your data watching Trad shooters is nice. But, have you controlled all the variables?
Ray Hammond makes some very good points.
No one is saying that you have to shoot skinny carbon arrows, that are point heavy with high FOC, and single bevel broadheads to kill game. People who don't use this type of set-up kill stuff all the time. If you are happy with the performance of your set up, that is fine. You don't have to be hunting asiatic buffalo to need the advantage of a better penetrating arrow. Ever hit a deer in the thick part of the shoulder blade or backbone and failed to get sufficient penetration to kill the animal? I have...and experiences such as this lead me to look for a better penetrating arrow as well as improve my shooting skills so the arrow goes where I want it to go. But let's face it, our arrows don't always end up where we want them to go no matter how good of a shooter you are. A better penetrating arrow can make it possible for persons who have limitations on how much bow weight they can handle to be able to effectively hunt an animal that otherwise may be considered too big...such as shooting elk with a bow less than 50# draw.
It is almost impossible to have a constructive conversation on Dr. Ashby's penetration studies without the thread being highjacked by those who disagree with his observations and findings. On the other website he gets treated worse than Sarah Palin showing up at a Democratic fund raising event!
JohnV writes: "It is almost impossible to have a constructive conversation on Dr. Ashby's penetration studies without the thread being highjacked by those who disagree with his observations and findings. On the other website he gets treated worse than Sarah Palin showing up at a Democratic fund raising event!"
Interesting comparison.
Here's what I see has happened to Sarah Palin: she has been demonized, along with her children. The reason is that people want to drown out her message.
I don't believe anyone here has demonized Ashby, nor are they trying to drown out his message. In fact, I've engaged his ideas, and only his ideas.
John, how is it that a "constructive conversation on Dr. Ashby's penetration studies" is hyjacked when people actively discuss exactly that? What you're saying is that anyone who disagrees with Ashby is not being constructive. Isn't that a mild form of Palinizing those who have a an opinion different from yours?
When I saw the subject "Tip for you Ultra-EFOC tinkerers", I passed it by and looked for subjects that I was interested in. Once the reply count got a bit higher, I thought I'd check out all the hubbub. I wasn't going to post anything here since nothing I'd say would apply to the original post (especially since I didn't even know what FOC or EFOC even meant until I read this post and Googled it.) After reading all the replies and (for lack of better word) bickering, the little voices in my head wouldn't let me walk away without saying this...
If you're not an EFOC tinkerer, why did you even feel the need to come here and post arguments, especially when you let it get off on tangents?
sorry... I'm confused.
Rusty