Trad Gang

Ok,

This question is for all of you fiddlers with  and tuners of arrows.  I have a 30.25 inch draw length. I shoot a 55 lb reflex deflex longbow with bamboo core limbs  I am presently using Axis FMJ 500 arrows with 275g grains up front and I am getting 21.5% FOC.  I just read up on a post that covered footed shafts and it stated not to glue them in for to much of the foot length or it would stiffen the shaft spine.  

Here is my question.  Since the foot can stiffen the arrow a bit and I need to stiffen mine to be able to add more weight up front, Would gluing in 4 to 5 inches of a 7 inch oak footing stiffen and arrow enough for me to put 350 or 400 grains up front which would push me towards the 30% Ultra Extreme FOC mark?

I am fiddling with arrows and wanted some input prior to actually starting the testing process to see if I could get a higher FOC with my long draw length and arrows.  Right now the arrows are tuned perfectly and I can only add another 25 grains to the tip and chop them a hair to get good flight.  I need to stiffen them up a bit if I want to push my FOC any further forward

What's your draw length?

The easiest would be to cut them as short as possible and then tune by adding weight.

Can you switch out to a thinner rest plate?


And then the ultimate question is where is the point of diminishing returns FOR YOU?   If you're trying to get a hunting setup dialed in I'd suggest you leave well enough alone. (If I recall 19% is the threshold to get the EFOC benefits.)  If you're simply having fun then I'd say go for it and report back.

Good luck.  I'm trying not to experiment too much until I get some serious time logged in the woods and some meat in the freezer.  I'm being mildly successful.

My draw length is 30.25 inches.  I have my hunting arrows dialed and I am not messing with them at all.  

I am already looking out a year and fiddling around to determine what I will be hunting with next year.  

The only way to go with a thinner rest plate would be to remove it entirely it is already really thin.

I am working up some Ultra Extreme FOC arrows for fun and to figure out if I can do it or not with a fairly long draw length.  I want the arrow to do at least 160 fps as well.  I may have to up my bow poundage to 65 lbs instead of 55 lbs to get the speed I want with the heavier arrow.    

I will keep everyone posted as I keep fiddling with things and let you all know what does and does not work for me.

Soilarch...I don't think 19% is threshhold for EFOC benefits.  The latest research suggest different... in a huge way. Not sure if the TOP has been reached at even 30% UEFOC.

Clay..I have also been hand loading a few arrows
to increase my FOC.  I am pulling 71-72 lbs at 31-ish inches.  I have built some GT 7595's with 27% EFOC that fly really well at 850 grains.
I also have a GT Big Game 100 that is 850 grains at 29.3% EFOC that bareshafts excellent with a broadhead...and flys excellent with 3 in. turkey feathers as well. It shoots 172 fps.
The baddest medicene so far is a GT Big Game 100
that is 995 grains and 31.02% UEFOC.  It is a serious weapon that really hushes up my widow recurve as well.

Getting the most FOC out of your arrow has to do with weight management as well as the sweet spot of fulcrum length.
It is not ALL about cutting your arrow as short as possible and then adding weight to weaken the spine and get FOC.
I have one arrow that is 28.?? % EFOC and weighs 881 grains.  Another that 29.3% EFOC is 1/2 inch LONGER and weighs 850 grains.  The length of the lever can allow for higher FOC...IF you get a stiff enough arrow that will allow you to keep it long.

Richie

Ok, you want to first cut the arrow as short as possible. Then add the entire oak dowel as internal shafting. Both will stiffen the spine weight so that you can add more point weight. To get the right spined dowels just weight 1/4in oak dowels and the dozen closest in weight will be closest in spine weight. The other thing you could do is buy a heavier spine weight shaft and add extra point weight. BTW the internal oak shaft make the arrows almost indestructible. It's like the internal footing on steroids. You might want to glue it in though otherwise they can pop out and push your nock out.

ummm.....you have to build out your strike plate to stiffen your arrow, not make it thinner.

Clint, you beat me to it.

Now this thread has one aspect that really interests me that I'd never heard of before.  The use of the wooden dowel inside I HAVE heard of but not that it can stiffen the arrow if you glue it in place more than a couple inches.  That is great news for me if it works.

I've tried carbons starting last year and have some CE heritage 350's which are about as stiff as I can find but since I only cut 3/4" off the raw shaft, I have a hard time getting the point weight I want.  With 100gr brass inserts, I can't go above 125 gr points or they are too weak.  I'd like to hear more about the glued dowel and how it stiffens the arrow.  I understand the concept that it's like shortening the arrow because there is less length of arrow that can flex but how much can you push the concept.

Clay, if you try it, I'd be interested in the results.  Oh, and sorry for butting in with my own questions....

Richie, you're close to my set up.  Actually you are shooting a bit more weight but I'm pulling farther.  (actually been working on shortening up a bit)  My bow is 65 at 32, hybrid longbow with FF string.  I'd like to end up about just on the short side of 800gr total.

Last spring the thread , "Perfect Arrow"ran here,30 or so pages long. Adcock and Ashby. The wooden dowel thing was to make arrows almost indestructable. I made a couple and yes they are tough, but they are noisey. Others on here had the same result. A noticeable click or clack upon release, not from being too stiff but from internal footing clanking inside the shaft as 5 inches of the footing floats inside to allow for flex. My hardwood I F's weighed 27 grns. Fun experiment. Tom

I understand that the "perfect arrow" was done with a tapered dowel with the intention of making a tougher arrow.  But if the intention is to use a dowel to stiffen spine only then it wouldn't need to be tapered and would be glued all along its length thus the noise issue should disappear.

Another thought comes to mind over this difference as well.

If you use a hard heavy wood then you're putting a lot of weight further back up the shaft.  My thinking here is that by using a light weight wood you could stiffen the static spine at the front of the arrow, while at the same time effectively moving the BOP back thus increasing dynamic spine while minimising the weight used.  That weight saving can then be added as point weight to increase FOC further.

My thoughts are using something like balsa.  Parralel internal footed and glued it's whole length should stiffen the spine quite dramatically while adding very little weight back up the shaft.

Just some thoughts, haven't tried any of this as i can't afford to keep buying carbons.

Ive got Ulta EFOC and only one way I could but have given thought to the IF too.

There are carbons out there of very light GPI yet of decently stiff spine.

Not only is the weight up front giving you higher FOC, LESS weight behind is as , if not more, important once you reach a certain point with EFOC.

Agreed, building OUT the strike plate is a huge leap towards it as well and I did so on my heavier bow.

I can take a very light GPI shaft spined FOR my 55, add over 350 grains up front, build out the stike plate (less than you would think too) and shoot an over 30 percent FOC arrow out of BOTH my 55 and 43 (not built out).

An additional plus of the very light GPI is you wont end up with a 800 grain arrow either. Mine are 585 grains.

Fly? oh my do they fly NICE. Not all agree and we never will on all subjects but the higher FOC I get, the better I shoot.....at all ranges.

Stability, even with very short, very low fletching is more than adequate and CAN shoot Deadheads on those arrows (weighted) and they group the same and with my 1 inch wide heads.

A great deal of the stability is the result of the VERY short (less than 6 inch) "arm" the blades of the heads have to work with while the fletching has the leverage of using the remaining 24 (approx) inches.

Picking a spine adequate is needed but again, the lower the GPI is......the higher of FOC you can get with it.

That said, 25 percent is pretty easy to get and I think they are a great themselves and most Ive introduced to that set up are more than happy with them at that point.

The ULTRA EFOC is new enough that more info gathering will, in time tell us more, and the main reason Im going there myself is simply the love of "tinkering" but I have to say I'll never shoot another NOT at least high FOC.

Not for everyone, Ill never be the one pointing to anyone that anything they like is "wrong" or "inferior" and will defend everyone's choice long and loud as their right to do so and it obviously fits their shooting/hunting preferences so no changes are "needed".

It, like every bit of equipment we use, hunting method and choice of game.....is an individual decision and we need to support that right to do so as well, IMHO.

For Me?  Oh yeah........!!

Clay, several folks posting have it all correct.

Weight management is the key to getting very high amounts of FOC. Reducing weight to the shaft's rear is very important. You want the shaft's rearward weight to be as little as possible, concentrating as much weight as possible as far forward as possible. Low GPI shafts help tremendously.

Reducing the degree of centershot by building the arrow plate OUT; thickening the arrow plate; increases the dynamic spine. That is; it allows a shaft having a weaker static spine to tune properly, or the same shaft to tune with a greater amount of tip weight.

Yes, length of the IF can be used to stiffen the spine. With the IF's I normally use; 7" to 9" OAL, having the back 5 inches tapered, change in the dynamic spine is minor. As the parallel portion of the IF gets longer the spine is progressively stiffened. I've not used any IF's that went beyond 1/2 the shaft length, but there is a big stiffening effect at that length. IF length is definitely a factor that can be used for some 'fine tuning' of the setup.

There will be more Ultra-FOC test results coming in the next few Updates, including (in Part 6) what the testing so far suggest about the percent of penetration gain per 1% FOC increase, once FOC is already into the EFOC range. Next Update (Part 2) will be out in just a few days.

Ed

I can see where if you are pretty burly, shoot a heavy bow with a long draw and want some weight up front, it could be tough to find an arrow. I'm shooting a carbon foam long bow with a recurve riser 57lbs at 28 drawing to just under 30. I shoot out of that bow a 100lb+ GT with about 400 up front and it needs to be shortened a little, to about 31 3/4.I could shoot a lot heavier draw weight but what would I use for arrows? I prefer to have the arrow on the center line of the bow because I shoot so many different bows and arrows. And I'm almost out of arrow at 57lb.
One thing I noticed about IF is; if it is not mechanically connected to the insert and point  on extreme hits the arrow will fail right at the end of the insert where the IF starts. I used to use 1/4 allthread behind the insert but stopped when I had a couple come loose. I went to the 2nd generation brass insert from 3R and if I need more up front I drill and tap the insert in the back and add 8/32 allthread screwed and glued into the insert but not touching the shaft.
I wonder if some of the Ash shafts that the Doc mentioned in some of his earlier reports would be the the ticket for very heavy applications instead of IF in a carbon. I hear Ash shafts are very tough and spine heavy.

Guys,

I want to say thanks for all the input so far and keep it coming!  Reading thru this has given me a lot of ideas to try out.  I plan to keep using the FMJ 500's for right now.  Right after hunting season ends in late January I will build out my side plate and see what that can do for me.  Once I find the limit on side plate effect.  I will pick up some oak dowels and start fiddling with glue length on internal footings.  The Brass inserts and attachments with all thread is a great idea too.

Dave,  No problem bud,  ask away.  Any questions we can add to the discussion will definately help all of us find better answers.

I will say that I am really liking the idea of a 300 grain head with 100 or 125 grain insert backed by a 7 inch internal footing that is glued in for 4 or 5 inches of it's length to get the spine I need with a 31 inch arrow.  30.5 inches will leave me 1/4 inch of shaft in front of fingers at full draw.  

Downside here!  For me anyways, I love using tapes on the back of my arrows.  Makes it easier to find the misses on the 3D range.  I am going to have to man up and sacrifice this little bit of personal flourish and arrow finding assistance.  I will hope I can crank things up front enough to put the tapes back on later arrow runs.

Have fun with it Clay. I've learned a lot about arrow reaction and flight after a few years of tinkering with EFOC. It's certainly been an education and, though frustrating at times, especially in the early days, when I had no one to ask questions of, it's been a lot of fun. I now look forward to doing my setup development and tuning. Here's hoping you enjoy the mental and physical exercise equally well!

Ed

what brand arrow have the lightest mass weight but the stiffest spine?

I am shooting some AD HAMMERHEADS with a 100gn. brass insert and a 100gn.steel adapter, and a 165gn. ACE EXPRESS. plus I put in some lead shot to match my practice points.(just using what I had on hand).Total arrow weight is 750+gns. If I remember my FOC was about 27%-28%. This set up will fly like a champ from my 64" 58#@30" R/D LONGWALKER. Not sure on speed, I don't have a speed meter. This set up was easy to make and seem to be tuff as nails. I am not to savvy with all of this foc/efoc stuff but I do know that this arrow will fly as well as my other lighter shafts with just a 125gn. head.

Earl, there are a lot of options in light weight shafts. Currently I'm working with the GT Ultra Lights. For the heavier bows I've managed 32% with it so far, but I'm trying to get to at least 35%, for some testing. The higher the FOC gets the more difficult it gets to squeeze that next extra bit of FOC out of the setup.

Ed

Thanks Mr Ashby take care and God Bless

Who makes the GT Ultralights?  Gold Tip?

Yep, gold tip is the GTs

Ok, from what I can read on the web GT Ultralights have 7.4 gpi.  With a 31 inch arrow, 300 grain tip, 125 grain insert, a 9 grain nock, and 4 - 2.25 inch fletchings at 9.6 grains with center of mass at 2.5 inches forward of the back of shaft for thde fletch I can hit 30% FOC on the head.  

This will make an arrow that weighs 673 grains.  This will crack the 650 grain bone breaking threshold and have what a few years ago would have been an insane FOC.  

I am interested in finding out what shafts out there have a tapering shaft.  I know about the Alaska Bowhunting Supply shafts and may look there for making something work to increase FOC.  What other carbon shafts are available with a tapered shaft?  Any?

I would prefer a shaft that is American made.  The grizzly stiks are made in China.

Clay,ARROW DYNAMICS are made in Kansas if I am not mistaken. They have many options for shafts and we have more than a couple sposors on the gang that sell them. Raptor Archery is one and Badger Arrow is another.

Question: Clay will the GT Ultralights have enough spine to fly straight at that much FOC from say a 55 to 60# bow ?

If you go around to wheel bow shops you can sometimes find the GTs with the flag on them. The only tapered that I know of are ACEs and maybe x10s which are very small and very spendy.
Lately I've been using Beman ICS and I've seen these arrows take some hits no others I have could. I don't think there that much heavier and last time I checked there made in Utah.
One has got to be careful about cheap arrows though as I've had some split at the noc on release from a very heavy setup with a fast heavyweight bow. It is very near a dry fire.

Earl Jeff, I think they make GT ultralights all the way to 300s. Depends on how your riser is cut and how much weight you put up front.
Man I've gone thru a bunch of candy tonight! I'm going to run out. LOL

Earl,  

Right now I do not know.  From Dr Ashby's recent posts and some deductive reasoning, I think they will spine out stiff enough if I build my side plate up a fair amount. The questions is how much.  I plan to try and see if they will spine stiff enough with the side plate build out.  If I need a stiffer spine, then I plan to start fiddling with internal footings with 4 or 5 inches of the IF glued in place for stiffening.

If that fails then I will look to the Arrow Dynamics and see what I can do with them.  

Right now it is all theoretical and field testing will be required to help determine the answers.  I can say it is exceptionally helpful to have Dr. Ashby and the other experienced people posting and helping those of us new to the FOC game understand where to start and where to look for answers.

I can say they will not be stiff enough at all if I try and shoot them with my bow with it's 1/8 inch short of center cut out.

GT ultras 300 are 8.5gr per inch, 400 are 7.4

Two Tracks,

Who makes the Arrow Dynamics?  Are they the arrows or the company?

Thanks

PSE X force 200 arrows are 7.5 gpi spine for 29" arrow is suppost to be good for up to 63#

checkout carbon express (line jammers) they are 7.6 gpi with a spine of .376 which means they should be good up to 70# with a 30" arrow. they are a little pricey but should be fantastic for EFOC setups.

Clay, Made up some 55/75 GT's and some AD trad lites, full lenght. 100 grn. brass, 275 tip. Both weighed same 742grn. with about 20% foc. To get 30% foc out of an AD I'm pretty sure you will end up way over 800 grn. Great shafts but hvy. to start with.

Just for what it's worth. I picked up some Patriot carbon shafts. 45/60 spine, (.435)that are 6.98 PGI. I think Git-r-done is the only place I could find them and the website for the company is no longer there???

Ive heard some neg comments on them but still looking for some "trial" High Country (Pro?) shafts that are "up to 80 lbs" but am sure thats quoted with their also ultra light heads but the GPI is 5.5. I also don't know the deflection in inches.

They also are not cheap like some others mentioned and finding A FEW has proved impossible.

As yet Im not in the position to commit to even a half dozen of these. Unemployment stinks.

Ive two bow weights to shoot but curiousity has me wondering just what Ultra EFOC one could get with that GPI shaft.

The "alledged" brittleness reported by a few to me might dictate an IF would be needed and sooner or later Ill find a few to find out.

God bless.

The arrow dynamics(AD) shafts are the shafts and company. They make many size shafts that are all tapered. from very lite to the HAMMERHEAD That is already "FOOTED" from the factory. it is thicker and stronger by making it with more carbon on the busness end. I am not  too savvy with all of this EFOC stuff but I wanted an AMERICAN made shaft and have had very good luck with the AD's for about 10-12 yrs. I shot them years ago and loved em then, took a brake from them but got into the heavy HAMMERHEADS this year and am well pleased. With very little thought and work I was well above 25% foc and remained under 800gn.(about 754gn). They are TUFF shafts. worth a look. Call Ted at Raptor or Paul at Badger Arrow. Ted had a large part in the developement of the HAMMERHEAD and is pretty up on all of the AD stuff.
P.S.
  My HAMMERHEADS are cut to 31.25" from 100gn brass insert to nock throat. I mounted a 165gn ACE EXPRESS to a 100gn. steel adapter, added some lead shot and ended up with a 747gn arrow. and if I remember my foc was about 27.8%

Dr. Ashby,
What about shat diameter, wouldn't you be better off with skinny Axis at 9 gpi than a fat shaft at 7.5 gpi?

Scott, when average penetrations are actually measured there's no difference in tissue penetration between a shaft that's 5% smaller than the broadhead's ferrule diameter and one that 25% smaller than the broadhead's ferrule diameter. In some materials, such as most foam targets, which are designed to stop arrows by shaft friction, the surface area of the shaft becomes very important in the penetration shown, with very skinny shafts out-penetrating shafts even slightly larger in diameter. That difference does not show up in the measured tissue penetration. Fresh tissues are a blood-suffused environment, with the blood acting as a lubricant, reducing the frictional coefficient.

As long as both shaft's have a daimeter at least 5% smaller than the broadhead's ferrule there will be no consistent, measurable difference in tissue penetration. On the other hand, the degree of FOC; once FOC reaches 19% or greater; has an enormous effect on measured tissue penetration, and the lighter the shaft, the easier it is to get higher amounts of FOC.

I hope I explained that clearly enough to be understandable.

Ed

Ed, thanks for the explanation.  I was thinking more along the line of splitting bone.  I'm shooting 23% FOC now but would have to go to a larger diameter for more...bone really is my only concern with the bigger shaft.  Any thoughts on bone hits?

Dr. Ed....That makes perfect sense.

As I have mentioned before I am using the GT Big Game 100's at 10.6 gpi and .280 deflection.  What arrow is available that is lighter per inch with a spine of .280 or less?

Hay guys I've been burning up the computer since yesterday the best weight to spine in a arrow I can find is the carbon express line jammers model 250 7.6gpi with a spine of 0.376 dia. is .386
http://dev.carbonexpressarrows.com/cms/content/linejammer

Ok,  I have been crunching numbers, checking out arrow shafts and reading up on some things here on Trad Gang.  Terry has some 29.5 inch Beman ICS 500 Bowhunter shafts at 7.3 gpi, with 350 grains up front and 4 -4 inch feather fletch that are pulling right at 29% FOC per his post.  

Running this shaft for my 31 inch arrows gives me a 226.3 grain shaft, a 9 grain nock, 2-3 inch fletch and 2-2 inch fletch = 8.4 grains, 5 inch tape = 7 grains, 100 grain brass insert and 300 grain head gives me a 650.7 grain arrow with 28.77 EFOC.  I am running out of options to crack the 30% UEFOC barrier with standard carbon shafts.    

I will get a hold of Ted at Raptor.  I may have to drive the hour he lives away from Vancouver, WA to chat with him on this. I am wondering what the lightest AD hammerhead shafts would weigh at 31 inches. I don't want to crack the 650 grain weight barrier for my arrows.  

I am shooting 55 lbs and want to keep my arrow speed up as high as possible while finding my maximum FOC with a 160 FPS arrow. I am willing to drop to 150 fps but would prefer not to. I am also planning to fiddle around 8 strand strings this winter in the off season to pick up a little speed that I am loosing to extra arrow weight.

Clay...If your arrow already bareshafts well with the 28% EFOC you should not need four feathers to stabilize it.  If you cut back to 3-3 inch feathers that should increase FOC to maybe 29.??%.
It all depends on how well it flys without any feathers first.  The already high FOC has alot to do with that arrow stabilization.

Richie,

I agree that 3 four inch fletch should not be needed.  I am having good luck using a four fletch with 2.5 inch feathers with my field points on arrows with 21% FOC.  I plan to try them with broadheads here shortly to see how they control the arrows.  The next step will be to try a 90 degree fletch with 2 2-inch and 2 3 inch fletching set at 75-105.  

I just ordered 2 dozen Beman ICS Bowhunter shafts to try out different set ups on to see what I can get out of them and maintain good tuning.   I am looking forward to finding out just how much I can load up the front end before I can no longer tune them properly.  Rob Distefano has some that he has loaded very heavy up front and is getting good flight out of.  

I think that someone with some math skills may need to run some numbers and tests when all of this is done to see what effect FOC has on arrow tuning, etc....

Sounds great Clay...make sure you let us all know how your work turns out.  It certainly is great information.

What is the spine deflection on the Beman ICS you are using?

My latest custom arrow is 1020 grains with 31.2% Ultra EFOC.  Just as sure as I am writing this now...that arrow flys just like a 750-800 grain arrow out of my bow, 71@31.  I am convinced the super high FOC actually makes the arrow fly flatter than NON fOC arrows.  I was amazed. And that is with 3- 3 inch feathers and 675 grains up front.  The speed seems faster than I thought as well.  I will try to chrono it today.

Bottom line is I can tell you I have noticed a significant difference in tuning with Ultra EFOC.

Richie,

The Beman Bowhunters I ordered are 500 spine arrows.  

When you get your arrows chrono'd post the numbers on this thread if you would.  I am interested to hear what speeds you are getting.

 I have a buddy building me a heavy oask sawhorse and I plan to build an bow firing system on it so I can repeat each shot at specific draw lengths.  I should have the whole thing put together in a couple weeks.

The plan is to work on getting exact numbers on velocities that are possible with various EFOC arrows and differing string counts and materials.  I also plan to test the theory that equal weight EFOC and normal FOC arrows fly differently.  The laws of physics say otherwise. I figured I could set up the sawhorse system and bow to hit a 40 yard target and see if one arrow hits lower than the other or not.  Pretty simple to test one way or the other.

The real goal I am pursuing right now is an arrow that is 650 grains or under with 30% UEFOC, or as close as I can get.  A secondary goal is to maintain 160 fps or higher velocity. Since I shoot a 55 lb longbow, that may not be possible.  Another secondary goal is to find the string count and material type that gives the best velocity and low string and bow noise. I know these are large goals,  it seems I am on an a personal quest for information which may never end.  

Upside, it sure is fun fiddling around and finding the answers.

I built a device that centers an 1/8 drill down the center of the cedar.  Managing an  airport has enlightened me, you'd be amazed at how long drill bits can be.  Then i load the end with lead shot to weight the end w/o stiffening it.  I also had a jig to band saw a cleft in the shaft to add an oak splice, but weight vs spine didn"t work for me.  Some thoughts....

Chrono numbers below with PSAX Widow 71-72 @ 31ish. I used 300 gr. field points (15 gr. less than broadheads) due to only target available.

1005 gr. 31% UEFOC   159 fps.

835 gr. 29% EFOC   173 fps.

I would like to know if I am just seeing things or if the Ultra and EFOC arrows fly better at equal weights.  It may be all in my head.  Let me know.

Hey Roadkill, are you using some of those 12" #30 drill bits?  PM your address and I'll send you something that works much better than shot.  1/8" dia and 35 gr/in.

Richie,

you will need to define what you think flying better is for me to answer that question.  

If you mean that the arrows are hitting in roughly the same spot when fired elevation wise.  Physics says not a chance.  The 24 fps difference in velocity alone guarantees that when aimed identically the 1005 grain arrow will hit lower.  That along with gravities effect on the arrows mass means the 1005 grain arrow will also hit lower.

Those are some awesome speeds for those arrow weights. At what distance are you noticing the arrows start to really drop off while in flight?

Thanks for posting the info, the numbers are giving me some other things to think about.

Richie, that 835 grain arrow doing 173fps should be a nice "compromise" arrow.  Great speed for that weight arrow.... Trajectory should "feel" like shooting about a 550gr arrow out of a low 50's poundage bow but It'll hit a heck of a lot harder!

Now, go out and try the internal footings glued in to see what sort of spine increases you can come up with so I don't have to....

fwiw, i think efoc is THE way to go, here's my setup and comments ...

bow holding weight: exactly 55# @ 29", 62" t/d mohawk mild r/d longbow.

shaft: beman ics 500 venture/bowhunter shafts at 29.5" from the nock groove to the front end of the shaft tube.

back of arrow: bohning nock, chopped 4" banana lo-profile 4 fletch with only a very slight offset.

front of arrow: 125 grain wensel woodsman, 125 grain stainless steel adapter, 45 grain aluminum insert.

inside shaft tube, directly behind the alum insert: 155 grain weight tube.

total arrow weight: 665 grains (+/- 3 grains)
 
arrow foc (@ 23.3"): 30.34%

arrow gpp: 12.09

at least for me, all that added front end weight doesn't affect the dynamic spine of the arrow.  as long as my release is reasonably clean, the arrow flight is dart-like and true.  as compared to my usual 585 grain arrows, these 665 grain arrows noticeably dig in deeper to a foamy butt at 20 yards.  the added 20 yard trajectory is quite slight, and not a problem to adjust my aiming.

hope to make good use of these arrows next week on a hog hunt.

Clay,
The arrows just seem to shoot flatter longer.  I don't know..I am beginning to think that maybe they just shoot better than I was expecting but not better than physics would say.  

Also it may be that I am used to seeing my 2317 aluminums fly instead of these skinny projectiles with such small feathers.  I will just keep this ghost of a theory under my hat until you prove it one way or another.

You just keep your research going as I conitinue to be an APSW.
(Arrow Projectile Scientist Wannabe)

Dave,
That 835 arrow (850 w/Grizzly head) shoots really flat for 20ish yards.  It does have it all...weight, FOC and speed.  It would certainly leave a mark on a good size rabbit.

But you know Dave...hand loading these custom arrows won't do much good if we can't keep up with our bows..now can they.

The EFOC arrow may well be flying better because it recovers from paradocs faster and will not scrub speed flying sideways.

I'm working on arrows for Connie.  She has a short draw (25.5") and limited weight (40 @ 25.5).

I'm working with some Trad .600 carbons.  So far I can get them too fly but am not satisfied.

They are cut to 28.5 and we have been shooting 175 gr up front.

I think I'll try some 250 gr heads today and see if we can get them smoking.

I'll let you know.

Mike

Well teh 250 gr showed weak.  Ran out of light.  Dropping to 200 in the morning too see where they go.

Mike

mike, try the 200 front end and slip in a 5" weight tube loaded with a 40 grain nail - make sure the nail in the tube and the tube in the shaft fit *tight*.  

doing so, you might find the arrow is just as stiff as before, only 55 grains heavier.  internally footing the carbon shaft seems to negate some of the added internal tube weight.  much experimenting can be done with these weight tubes ....

Rob,

What speeds are you getting with your arrows?  

How significant do you think the stiffening effect of the internal footing with weight tubes is for your arrows.  Do you think the stiffening effect have more effect on the arrow spine than having great form and a smooth release?

Does the footing you use stengthen the arrow shaft like the oak ones that OL Adcock posted about?  

Using Axis FMJ 500 Shafts at 9.1 gpi, I am really struggling to get over 21% FOC.  With 500 spine Beman Bowhunters, I should easily hit 26% and may reach 30%.  The reasons I am using the FMJ's right now is that they are incredibly tough and easily hit the minimum weights I was looking for in my arrows.  So I would love to be able to work up some beman bowhunters with the knowledge that they will be plenty tough on Elk or Wild Hogs.

clay ...

i have no clue as to what actual fps speeds i'm getting outta any of my arrows ... sold off the last chrono a year or so ago.  it took me too long to realize none of that technical speed stuff matters.  when it comes to arrow speed, i use the chrono built in between my ears.  

for woods animal hunting, i'm only concerned with how the arrows fly at distances up to around 25 yards or so.  if i up the arrow weight, i need to feel comfortable with the loss of speed and increased trajectory.  going from an arrow totaling 585 grains to 665 grains wasn't a big deal for me to get used to at even 32 yards, let alone 15 yards.

after shooting 155 grain 5" weight tube arrows a whole bunch (into a foam butt with field points, and roving around with judo heads), i don't think spine is compromised at all, and may even be increased a tad.  here's the important caveat: FOR ME (not you or anyone else).

i think adding most anything internally to the arrow shaft, behind the head, will strengthen that area of the arrow.  hey, it's a 'footing' of sorts.

there is NO SUBSTITUTEfor a smooth release and a good 'hunting form'.  

if yer nagged by release/form issues, and you wanna up the foc, add in a full length unweighted weight tube to stiffen up the arrow spine, or go up to the next size stiffer shaft to accommodate yer newly added front end foc weight.    

i want to use a carbon shaft that will allow me to concentrate a LOT of weight at the forward end, yet still allow the total arrow weight to yield a good gpp for my bow's holding weight.  for me, the beman ics 500's offer good tweakability, are pretty darned durable and are bottom feeder cheap.  

a 665 grain arrow is 12 gpp for a 55# holding draw weight.  that's the kinda numbers i like for tough critters like hogs, at relatively close shooting distances.  

if the hunt was for open prairie speed goats, i'd wanna opt for a flatter shooting arrow weight of 500 to 550 grains and 9 to 10 gpp.  gosh, i'd love to kill an antelope some day ... such good bbq eatin'!

all this stuff about arrows - total weight, foc and dynamic spine - is going to be personal to each of us and we each need to put in the experimenting and testing time, IF we care to ... else, don't bother and just shoot what ya got.  all depends on yer wants and needs.

a somewhat related note: the new tbm features an article on the 'flemish 2 finger' string grip, as opposed to the more standard mediterranean 3 finger string grip.  basically, that's what i use.  the ring finger of my string hand pretty much just goes along for the ride, just touches the string and almost all of the string's holding weight is on my middle finger.  this is much closer to using a release aid and helps me achieve a much cleaner release, specially when hunting in nasty venues and weather, and my form is suffering.

Rob,

Don't have any weight tubes for these smaller diameter arrows.  Rusty gave Connie these .600 and they are different then any shafts I've had before. Was thinking about checking out Home Depot this morning and seeing what I can find in plastic tubing.

Mike

mike,

really small id, eh?  when i was looking around for what kinda tube would fit the beman ics, i found some plastic soda straws that had too small an od - might work for ya?  aquarium tubing?  

the carbon express 3 grains per inch tubing i'm using is a good fit for the bemans, but still needs a full wrap of blue 3m masking tape for a *snug* fit when ramming the tube deep into the shaft.  dittos for wrapping the 16d nail, for a tight fit into the weight tube.  

can't stress enuf the need for a *tight* fit of all the components of a weighted front end tube.

good luck!  you'll find something, for sure!

r.

Mike the 5/16" brass tubing found at hobby stores will probably slip right over them for an external footing and point weight boost.  That's what I use on our Predator II 20/40's and 30/50's, just epoxy them on.  Make sure you've got your arrow length right before you do that, and I'd suggest you put the brass foot on before installing the insert.

Well we got it!!  Went to the 200 gr point and a small nockpoint adjustment they are flying like well. . .arrows.

She's set now.

Gotta get the rest of the BHs mounted and touched up.  Going down to Gil's next weekend to get a doe or two and maybe a hog.

Thanks for the help!!

Mike

I just picked up the 2 dozen Beman ICS Bowhunters in 500 spine I ordered from my local archery shop.  I planned to make up several sets of arrows at 9, 10, 11, & 12 grains per lb for some speed and shot noise testing I am working on.  

I ran some numbers and it looks like I can set up all the arrows with 100 grain brass inserts at a full length of 30.5 inches.  I plan to use 4 - 3 inch fletch set at 75/105 and the standard nocks.  I can adjust the weights of the arrows very close to 495, 550, 605, & 660 grains by changing the heads out to 145 grains, 200 grains, 250 grains, and 300 grains.

Using the varing weight heads and running some FOC #'s The varying weight arrows for 9,10,11 & 12 grains per lb will give me

9 gr / lb - 495 gr - 19.7 %  

10 gr / lb - 550 gr - 25.3 %

11 gr / lb - 605 gr - 27.6 %

12 gr / lb - 660 gr - 29.4 %

I have to work up the basic arrows and then test them out for where they spine out right.  I am also thinking I can run outserts from aluminum arrows for external footing or work up oak dowel footings to stiffen the arrows if I need to.  Either way I have what I need to get started on the arrows.  These arrows will also allow me to run the other testing I have planned.

I will keep this thread updated as I move forward and find out what the actual foc numbers are.

I have several bows in the 52#-57# range that I have been experimenting with on the EFOC principle. Here is my experience FWIW. I have tried in vain to get GT 35-55's and CE 150's to fly well regardless of how I try to stiffen up the front. However, the GT 55-75's shoot well out of all of the bows by varying length and point weight slightly.  The best I have been able to achieve so far (EFOC) is a shaft cut to 28 1/2 with 100 grain brass insert, 100 grain steel adaptor and 190 grain broadhead.  This gives me a total arrow weight of 650 grains (the magic number for bone threshold) an EFOC of 29.8% and a gr/lb of 12.2 from my 53 @ 27" Moosejaw. My chrono says the arrows are traveling at 154 fps and the Grizzly El Grande 190's shoot right with the field points, using 3 4" shield cut fletches. My "lightweight" setup is my 52 @27 Liberty Elite with the arrow cut to 29 1/4, a 50 gr brass insert, 100 grain steel adaptor and 160 grain broadhead (Grizzly or Ace).  Total arrow weight is 566 gr, giving a 10.9 gr/lb, 27.8% EFOC and flying at 160 fps, requiring virtually no adjustment in aiming between the two bows, both of which are cut 3/16" from center shot. I'm using 3 3" parabolic  fletches on the arrows for the Liberty. I really like how these combinations are shooting, but I love to play around with this stuff, so I'm sure my experimenting is not over. Getting the right arrow and having it tuned correctly has helped my shooting consistency immensely.  Now I know that if I miss my target it is not the fault of the arrow and I can critique my form to determine why the miss.

Ok,

So the arrows are made up.  

I have two dozen full length 30.5 inch beman ICS Bowhunter 550 shafts.  100 grain brass inserts, 3 - 3 inch shield cut fletch, standard Beman nocks, and a 4 - inch flourescent orange tiger stripe tape on each arrow.  YAH I KNOW, I should drop the tapes to increase FOC.  Especially since the arrows cost less than half per dozen what my FMJ's were running.  I just like tapes on arrows, particularly when I find myself searching for them behind a 3D target.  I have the arrow shafts within 0.2 grains of each other.

So based on the last posting above I can say the actual FOC% numbers are pretty darn close to the calculated numbers.  I am just waiting for Brock over at Bull Mountain Archery to complete a new 8 strand TS+ and a 12 strand TS+ string for me.  Once I get those shot in and fully stretched.  The bow and arrows will be ready for my testing runs.

A buddy is building me a tall sawhorse to build an arrow holding / firing device.  I plan to set it up so I can draw the bows to specific draw lengths in half in increments.    

Real world results for the EFOC arrows will be posted before long.  I want to get the tuning process and final arrow lengths / weights figured out before posting any numbers or results.

Deer and Elk hunting are almost over here so it is time to get on with this process.

Is any of you still using the turbulator? Thanks.

God bless,

José

I made a 29" gold tip ultra lite that flies great out of my bow. 365 grains up front 640 total can you tell me my foc and would that be concidered extreme?

QuoteOriginally posted by elktalker:
I made a 29" gold tip ultra lite that flies great out of my bow. 365 grains up front 640 total can you tell me my foc and would that be concidered extreme?

you need to first find the arrow's balance point in order to determine its foc ...

http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=2;t=000089

QuoteOriginally posted by elktalker:
I made a 29" gold tip ultra lite that flies great out of my bow. 365 grains up front 640 total can you tell me my foc and would that be concidered extreme?

According to stu miller's calculator, you have about 26.4% . W/O knowing which spine I played a little. Are you shooting the .300 spine? Your bow is about 55# at 28"?

the arrow is a 300 my bow is about 62# @ my draw.(65# @ 28)balance point 22.5

the ONLY true way to calculate foc is to know the total arrow weight, the precise arrow length (from the depth of the nock groove to the end of the shaft (in the case of carbons or alums, end of the arrow insert), and the distance between the depth of the nock groove and the arrow's balance point.

(http://www.tradgang.com/docs/arrow_calcs.gif)

foc and gpp spreadsheet (http://www.tradgang.com/docs/arrow_calcs.xls)

thank you for the foc and gpp spreadsheet I didn't know you could input #s in the first time I looked. My foc is 27.5

QuoteOriginally posted by jdemoya:
Is any of you still using the turbulator? Thanks.

God bless,

José

HAH!    :biglaugh:

sorry, just had laugh.

'turbulator'?   ummm,  no thanx.     :rolleyes:      

What, Rob? You still havin too much trouble getting the J4 bottles to balance on the rear of your shaft and clear the shelf???

QuoteOriginally posted by Doc Nock:
What, Rob? You still havin too much trouble getting the J4 bottles to balance on the rear of your shaft and clear the shelf???

:knothead:    :biglaugh:

This is my first post ever on trad gang so hopefully no social faux pas will be committed.

I just decided to get back into traditional archery after a 15 year hiatus and hit the net to research what's changed in that time. I too became intrigued by the foc studies Dr. Ashby has done. (BTW Dr. Ashby my thoughts and prayers go out to you. I hope 2010 returns you to full health and faculties.)

Like a few other posts here I have been struggling to break the 30% barrier. Last night I came across Dr. Ashby's notes on the Papua New Guinea hunters and their equipment...check out his post on Alaska bowhunting  http://www.alaskabowhunting.com/PR/Ashby_Papua_New_Guinea_Bows_and_Arrows.pdf

After reading that it dawned on me the reason this Ultra barrier is hard to breach is because our broadheads size (length) and weight is inadequate.

Much of the weight we add is in the shaft (heavy inserts) where it loses much of it's effectiveness due to it's proximity to the balance point. Basically we need our broadheads weight to be further forward.

Tonight I got home from work to find my 190gr Grizzlies and 125gr broadhead adapters in the mail. While dry fitting the insert I noticed that there was a void inside the ferrule in front of the adapter.

It dawned on me I could add weight to the ferrule near the middle of the broadhead moving the extra weight forward of the insert.

What I did...turns out #6 lead bird shot weighs about 2gr per pellet. I was able to melt down 16 pellets (32grs) in the ferrule with a propane torch and not interfere with the adapter. My FOC went from 29.5% to 31.2%

Here is the arrow set-up:
Beman Bowhunter 400 (8.4gr/in)
Shaft 28.5"
Nock throat to end of insert 29.25"
100 grain brass insert (sticks out 1/4"from end of shaft when fully inserted)
125gr steel insert
190gr Grizzly glue on heads
16 pellets of #6shot (although you can use any size since it will be melted)
3-5" feathers
Factory nocks (direct fit super nock)
Total Arrow weight 730gr

The result is 31.2% FOC

So a couple lessons learned...
1. have a plan on what to do with the left over powder if you cut open a shell like I did
2. don't melt the lead inside the broadhead. I fear I may have killed the tempering on the braodhead...now have a practice only head

Once I find a suitable vessel to melt the lead in, I will finish up a few more heads to see how they fly...I'll let you know.

Maybe I can get 1 or 2 more pellets in too....

Sorry for the length of the post.

Antonio great setup you might want to look at some Victory archery HV Shafts they have 350 spine shafts that are 6.4 GPI and try putting smaller shot in the insert you can fit more in to start and after they melt just keep the heat on them and those little buggers melt quick.

Do you know if my ICS inserts will work on their arrows?

With a slightly lighter nock and shaft I might be able to pick up a couple more %

Thanks for the tip!

I'm kinda curious as to why the length of the point is not used in computing FOC.  The point is used in the total arrow weight, balance point, and is a part of the flying arrow.  Why is the point not a part of the arrow's length?

Chopx2,
I mentioned that in another thread. It does work.  Textbook physics.

posted December 20, 2009 02:41 PM                        
--------------------------------------------------------------------------------
I totally agree with 30coupe.
Your FOC will increase the quickest if you get the weight literally out in front of the arrow instead of inside the arrow...AS IN...the broadhead and adapter. Then work backwards to 100 gr. brass insert and then weight behind insert if needed.

With glue-on Grizzlys I have put 15 grains of lead from bullet worm weights in the ferrule before glueing in adapter. Works great by adding more weight in front of arrow.

--------------------

Chopx2,
You can also use 3" feathers instead of 5" and cut 1/8-3/16" off male part of nock.  That will decrease a few grains from long lever and add to the heavy or short lever.  Increasing FOC.

Hey everyone, I am brand new to this website, and relatively new to traditional archery, and as you can imagine, I need endless help!
The Dr. Ashby studies got me fired up about trying to shoot a heavy arrow with Ultra EFOC. I would like to shoot 650 grains total (to reach heavy bone threshold) and 30% FOC. I have a bear Montana longbow, I am pulling 50# at 29 inches, I have easton aftermath 400's at 29.5 inches, but 225 grains is as much I can put up front before the spine gets too week. Total weight is only at 512 grains with FOC only in the low 20's. How can I increase my overall weight by 135 grains and keep my arrow stiff enough? From what I have seen, people are using as low as 7 GPI arrows achieving UEFOC, but my arrows are 8.8 GPI, so if I increase my spine to 340's, it will be that much harder to achieve UEFOC.
sorry for the long post, any thoughts or ideas will be greatly appreciated.

Thanks

Here is my question. Since the foot can stiffen the arrow a bit and I need to stiffen mine to be able to add more weight up front, Would gluing in 4 to 5 inches of a 7 inch oak footing stiffen and arrow enough for me to put 350 or 400 grains up front which would push me towards the 30% Ultra Extreme FOC mark?

I haven't read through this whole thread because i'm not much interested in the Ultra EFOC thing at all..... But..... to answer the question you asked here would be "Yes" it will stiffen things up, BUT.... running an over footing past your insert like that put's a hinge point on that arrows flex point, and under extreme impact conditions, will snap off right behind the footing....

I think i would look into possibly using full metal jacket arrows, or a tapered shaft like Grizzly makes rather than a long footing that cause a weak spot in your shaft.... food for thought.

QuoteOriginally posted by Earl Jeff:
what brand arrow have the lightest mass weight but the stiffest spine?

Victory HV series are the lightest ones I have found.

For my son's 50# bow, I built arrows that were 34+% FOC and weighed around 650 grains.  I started with a Gold Tip Ultralight 500 and used external footings. The external footings do well to stiffen the spine enough to achieve the FOC goals, properly tune the arrow and make a bomb proof arrow.

Pardons if I missed these being mentioned, but does anyone use the GT internal insert weight system? I have not, but they make a wrench where nocks can be pulled and weights added without pulling the inserts. Has anyone used it? I believe EFOC was the market the whole concept was developed around.  I know the jury's seems to still be out on end weight vs. internal weight relating to its effect on spine.  But from my limited experience tinkering, they do not act the same. Internal weight, if it's the same ID, seems to stiffen the shaft similar to footing and I can get away with more weight without weakening spine than I could if it was all up front.

Richard,

I have no scientific evidence or source to prove this, but I THINK the reason that internal weights "seem" to increase spine is that effectively, you're shortening the shaft in a fashion...ie, you're moving weight rearward...by increasing weight on the end of the shaft, you're having the same effect as lengthening the lever...adding weight out on the end...putting weight INSIDE, moves the lever weight BACK toward center, thus stiffening.

I avoid all that head work but using what insert I want, head I want, then start tuning at full length and cutting from the rear...

Don't know if that makes sense or not, but it's how it's worked out in my riddled brain!    :eek: