I understand the benefits of heavy FOC for additional penetration and tuning. However I wonder at what point the amount of FOC is detrimental to arrow trajectory and accuracy. I am moving up to #65 from #55. My bow currently has a point of aim at about 25 yards. I am shooting Easton 2018s with a 125 head. I hope to increase arrow weight and point weight with the new limbs. I worry that the heavy weight will make shooting accurately harder due to a rapid arrow drop after point of aim, If the arrow becomes so heavy that point of aim is closer than 15 or 20 yards I worry about being as accurate as I would like to be for taking game.
What are the experiences of those who have switched to heavier arrows and heads?
"However I wonder at what point the amount of FOC is detrimental to arrow trajectory and accuracy."
Actual arrow weight and FOC are not related.
Higher FOC's all else being equal will shoot flatter and more accurate. More weight will increase trajectory whether higher then normal FOC or not.
Higher FOC's make the arrows more stable but more stability above a certain point results in no noticeable gains in trajectory/accuracy so to take full advantage of higher FOC's is to reduce fletching size so you have the same stability. I suspect there are no negitive effects of getting as much FOc as you can....O.L.
I use higher FOC with carbons because they seem to handle that well.But I'm not totally convinced higher FOC works well with aluminum or wood.
I have found the trajectory to be a small factor and no real issue. Yes you get a flatter trajectory with a lighter tip but all you have to do is practice a tad bit more. a friend recently broke my stereo type about having to shoot matched arrows and all that, as a matter of fact i went and shot today with three different types of arrows. Woods 55-60# 30" with 125 grn on point, Carbons CE 150's 29.5" with 175 on point all shot 5 inch groups at 25 yards or so. And with no fish tailing. All that to say, pactice with your setup and it doesnt much matter. Now i am a EFOC guy and love it, every kill this year was with a complete pass-thru with the same arrow, on e at 15 and one at 28yards, i also bareshaft my carbon arrows....
P.
I guess my confusion comes from the total increase of weight when talking about super heavy broadheads. If you go from a 125 gr. tip to a 300 gr. tip the overall mass increases. doesn't that create a much greater, or sooner point at which the arrow starts to drop dramatically?
The idea is to use a lighter stiffer shaft and add as much weight as needed to the front to get them tuned . The arrow doesn't need to be heavier per say , just more of the weight up front . Drew
Yep, The best shaft would weigh nothing! Shaft spine increases by the cube of their diameter so going up a little in diameter increase spine a lot with little to no weight increase for a higher spine. The shafts we need haven't been made yet! :) ....O.L.
I think by adding all the wieght to the front of the arrow it does mess with trajectory. I shoot split vision, if I use a Griz stick or a tube wieghted arrow it seems to shoot flatter then every thing in the nose. That's just me, not sure what the deal is but it messes me up.
Thanks that helps clarify. I tried to use the chart and info on the gold tip site (thanks for the pm) but the arrow weight was to low. So by using heavier bh's I could get the total arrow weight where I needed and be efoc.
The total mass weight of your arrow is the main contributor to how flat the trajectory will be.
The EFOC affects how the arrow recovers from the archer's paradox, how stable it is in flight, and how it actually passes through game. (Extreme weight forward arrows actually reach a point of that forward mass pulling the rest of the arrow through the critter.)
It seems complicated, but one you think about it and read up on it it starts to make sense.
AlaskaBowhunting.com has been posting some excellent YouTube videos on the archer's paradox and Dr Ashby's reports are all posted right here on Trad Gang.
They're great reading! todd
It seems to me that the whole extreme FOC sitation came about because some guys tried to shoot the carbon soda straws they were used to with compounds out of trad bows.
Of course, the consensus was always to shoot X number of grains per pound out of trad gear and the carbon arrows didn't even come close. All sorts of methods were tried to come up with ways to add weight. Wether it was full length with tubes, rope, weed eater line, black pepper, you name it or front and rear with spacers, washers etc. I think someone finally just got lazy and put it all in the point and tried it in spite of the obvious "too heavy" FOC (by the old standards)
What does this have to do with your question? Well you have to compare light weight carbons to heavier shaft materials like wood or aluminum to make sense of it. Where you could get a 28 inch wood shaft with a 125 gr point to easily weigh 500 grains, the same point weight on a carbon soda straw would only give say a 350 gr arrow. (I'm guessing on the carbon weight but just figure it's a good bit less than a woodie.)
The funny thing was, when guys put massive point weights up front on the lightweight carbon arrow to make it equal the woodie, it flew far better than anyone expected it to. Trajectory whould be the same as both are 500 grains and trajectory is mainly a function of gravity and time(speed). Arrow recovery rate and other things are issues too but to keep it simple, just think of total weight and speed.
If you put a couple hundred grains of weight up front on a wood shaft, it would fly with the the similar stability characteristics of a carbon with the exception that because the shaft itself weighs a lot more, the whole arrow will weigh more thus trajectory will suffer at some point. The carbon will likely also have an advantage of recovering faster from archers paradox as that is simply a characteristic of carbon arrows.
Dave, "I think someone finally just got lazy and put it all in the point and tried it in spite of the obvious "too heavy" FOC (by the old standards)"
Been watching this for years and from what I can see it didn't evolve that way. It was intentional from the start because the physics and aerodynamics makes perfect sense.
"The carbon will likely also have an advantage of recovering faster from archers paradox as that is simply a characteristic of carbon arrows."
It's also a characteristic of high FOC's no matter what material the arrow is made out of. It's just easier and takes less creative thinking on the makers part to use carbon. Wood arrows footed with a heavy hardwood, light POC in the back, then tapered in the back, with 2" of tungsten rod drilled in behind the heavy point are the best thing since sliced bread! :) ....O.L.
O.L, where would one find tungsten rod? I have achieved high FOC with carbons and 125 grain brass inserts, 125 grain steel adapters and 125 grain broadheads, and quiet arrows using small 75 degree 4 inch, 4 fletch in a semi-banana configuration.
But I like wood arrows and also shoot bamboo backed osage bows. Going to need a lighter spine to deal with bend around the handle, tapered shafts and heavy footings to get near where I need to be. I like the idea of the tungsten rod from the standpoint of expense, ease of installation and practical way to get weight up front in addition to the hardwood footing. Thinking of using Sitka spruce instead of POC though (seem to be a bit tougher and I can get them straight and they stay that way, similar to POC).
Any suggestions on where to find the tungsten rod? I assume a jig with drill press to put in a straight hole in the arrow shaft.
I've been going thru all my arrows that are weight tubed and &*$#canning the weight tube. Then I have been using 1/4 all thread right behind the insert (fits in .246 arrows most of the time) and 5/16 on big eastons. I have been shooting heavy arrows, but not with any extra FOC. I decided to try it with some heavier bows and some 340 GTs and I couldn't believe it, it worked so well. I haven't had to shorten them yet but I might later. They recover so fast it is amazing. And if you hunt you will get much better penetration because there is very little parallax on the entry into the animal with the weight all up front.
The surprising thing is I haven't had to cut the arrows down to much, heck I thought I would even have to up size to compensate.
It seems on the eastons you have to put a lot up front to get the effect. I just put together some full length 2317s and at first I just tapped and screwed in a 21/64 150 grain field point in the back of the insert. There is just room to get a couple of threads. And then a 200 grain practice point to mach my broadheads. But they didn't fly too well and were tweaking left. So I did the opposite and took out the 150 grain weights and put in 300 grains of 5/16 all thread right behind the inserts. They have 500 grains up front and weight about 975 grains. They seem to have picked up the parallax effect although I am ready to cut off a little for more spine if I need to (hot glue during tuning). They do have a usable trajectory at 20 yards. I had them at an indoor range in a store the other day with a 65 lb longbow and I had to stop shooting into the league targets as they were going all the way thru and slamming into the wall which upsets the gunsmith in the next room greatly. I may have to bring a newer cube to stop some of the arrows I've set up for my heavy bows .
I've also set some up for my lighter stuff and that is going well too.
Bruce, Here is one source, you can do a Google search and find others: http://www.buffalotungsten.com/html/tungsten_rod.html
Yes, a jig to drill straight is what I use and you can mix and match steel, brass, or whatever to fine tune. I normally use .125" but have some .185" I think it is, it's 130gr/in so it's HEAVY.
I have some arrows that are supposed to be accurate replicas of early eastern US indian origin. Cane shafts footed with hardwood foreshafts...They are very high FOC so this is not a modern thing brought on by carbon arrows at all. More likely a desirable trait dismissed as being insignificant and too lazy to experiment with! :) The easy way is following the herd....O.L.
O.L. I'm sure you are right about the high FOC being deliberate in some cases but from what I've seen just from people I know and reading posts here, quite a few different folks were ending up that way just because they wanted a heavy arrow for penetration and not because they thought it would fly better.
Guys like you with a scientific bent to their personality certainly probably approached the whole thing deliberately but with tens of thousands of bowhunters giving things a try, certainly many just threw things together and were pleasantly suprised. Sort of a case of a little knowledge is a dangerous thing only this time it worked against conventional wisdom. And of course, by conventional wisdom I mean what was considered standard FOC for proper flight in modern times, not examples of primitive arrows 99% of todays trad archers will never use. I'm sure there are many things from the history of archery that have been nearly forgotten but get "rediscovered" in modern times and people think they are the first to do something.
You also said "It's also a characteristic of high FOC's no matter what material the arrow is made out of. It's just easier and takes less creative thinking on the makers part to use carbon. Wood arrows footed with a heavy hardwood, light POC in the back, then tapered in the back, with 2" of tungsten rod drilled in behind the heavy point are the best thing since sliced bread! ....O.L."
So...is it a matter of proportion of head weight to shaft weight only or do shaft material characteristics play a part? Does a heavy shaft "wag the dog" if the dog is to light so to speak? I know you have done a lot of testing and I'm just armchair quarterbacking but it seems to me that a lot of the advantage of the carbon arrows is simply the fact that it weighs so little causing a disproportionate weight difference with the head compared to other materials. Hence high FOC without exceeding normal overall arrow weights wich would cause trajectory problems. If I try to do the same thing with a wood shaft at my long draw length of 32" I can't get shafts strong enough and my finished arrow weight would be probably in the 800 to 1,000 grain plus range depending on type of wood. I think my trajectory certainly would suffer... :eek: regardless of how well the arrows stabilized. They certainly would blow through any deer I'm sure. Heck, even with standard tip weights, I've never left an arrow in a deer.
Oh yea, would the tungsten rod from a tig welder work? Not sure of the diameter off the top of my head but it's about .8" if I had to guess.
Oops, make that .08 I guess. a little under a tenth of an inch.
Dave, Some of the first tungsten I got hold of was given to me by a welder, it was about .125".
I have a long draw also and with POC arrows typically come out in the 500-550 range if left parallel. Are or can carbon arrows be "light", yep, but there are lots of heavy arrows out there also and yes, they are easier to play with simply cause they are hollow. Darned wood arrow don't come that way! :)
That's part of the challenge with high FOC's is no off the shelf comercial products to do it, or at least there wasn't just a few years ago. More are coming online which is a good thing. Some think if they want more FOC or more weight all they have to do is a heavier point, it doesn't work that way. FOC and overall arrow weight aren't related but requires planning if intentionaly targeting a specific weight or FOC or both....O.L.
So how does a newbie with no arrow making equipment do this with out investing more than the cost of a custom bow to get high FOC arrow that shoots well out of their bow?
Maineac, You are doing what you need to do right now...Reading how others are doing it. It's going to "cost" something, either time or $$$. A subject that goes along with shooting EFOC's is footings....They can go together and be one and the same. You got comercial stuff like inserts made of aluminum, brass, or steel, all different weights...You got broadhead/point adapters in aluminum, brass, and steel, again all different weights...Points themselves from 75gr to 300grs...Then for a few $$ you can go down to the hobby shop and get into the K&S tubing display and buy brass or aluminum tubing of many sizes to go behind inserts to act as footings and change FOC as well. I do a lot of my footings and FOC work with carbon from a company called ACP. This is still evolving with no "best" way identified especially what would work with one arrow type won't work with another. Creativity, ingenuity, and experimentation will go a long way......O.L.
QuoteOriginally posted by drewsbow:
The idea is to use a lighter stiffer shaft and add as much weight as needed to the front to get them tuned . The arrow doesn't need to be heavier per say , just more of the weight up front . Drew
agreed, that way you get all the advantages high FOC gives you without increasing the overall arrow weight and therefore not effect your trajectory.
A little trivia, just got off the phone with a 2004 US Olympic archery team member, he shoots an FOC around 21% and said all the top contenders do. "Trajectory" is a big issue trying to reach 90 meters with light bows....O.L.