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Extreme F.O.C

99K views 983 replies 161 participants last post by  KingofHeros 
#1 ·
I've been meaning to experiment with a higher foc, say 15% and more. So whose doing it, whats yor set up and whats your experience with it?
 
#3 ·
I tested high to extreme FOC's and due to those tests, am hunting w/an FOC arrow of 18%! First of all, my bow is tuned PERFECTLY! repeat, PERFECTLY, as this is critical for 'testing', e.g. I'm shooting Silver Flame XL 150's and they shoot perfectly out to 60 yds, just like my FP. For those of you that are not familiar w/this BH, its a fixed 2-bladed design that is 1.5" wide!

What I found out is this: I could use much smaller vanes w/this BH and it 'appeared' that the arrow flew perfectly down range. How small a vane? W/the XL150 I used 3 3d vanes! and the arrow flew perfectly--the AAE 187 vanes that I'm using for my 3d rig! I was REALLY surprised at this. Am I hunting w/this set-up? No, I sent w/3 mini Blazers.

PM if you want more info.
 
#796 ·
What I found out is this: I could use much smaller vanes w/this BH and it 'appeared' that the arrow flew perfectly down range. How small a vane? W/the XL150 I used 3 3d vanes! and the arrow flew perfectly--the AAE 187 vanes that I'm using for my 3d rig! I was REALLY surprised at this. Am I hunting w/this set-up? No, I sent w/3 mini Blazers.
With a higher FOC, naturally the balance point is closer to the tip end and farther from the nock end (and fletching). The farther the balance point is from the fletching, the easier it is for the fletching to steer the arrow - thereby allowing the use of smaller (and lighter) fletching (I'm sure the physics police from another world will find fault with this). I'm at 13% (with my measurement method) and I'd have to go to 125gr to get any more which I don't want to do.
 
#4 ·
My hunting arrows I set up two years ago were Carbon Impacts, with a weighted insert and 125 grain heads. They ended up at about 18% FOC. Shooting Shuttle T-Locks, I was breaking nocks with them at 30 yards. I also used those arrows on an indoor 3-d league where hunting equipment was required, and they flew awesome. I really like the higher FOC, even though they drop off faster at distance. They just seem to be more accurate.
 
#6 ·
I shoot just over 20%.
They tune well and fly even better.
I am currently building a couple of arrows to test the 'high FOC drops faster' theory.
So, two arrows, identical length, spine and weight, same fletching, one high FOC, one low FOC.
I will post the results over the weekend (weather permitting).

Kev
 
#7 ·
keep us posted on that one! Fita shooters use a higher foc (for better long range accuracy I assume) and got to thinking...... why doesnt everyone do that? Todays lighter GPI arrows make it possible to do this and still shoot a relativly lighter faster arrow thats still spined correctly. Anyone shoot High foc and still get 5 to 6 GPI?
 
#8 ·
I have alsoo been doing some EFOC experimenting myself. Not in the weight range you are talking but end up at around 450 grains. Also some around 525. One thing I did notice last year when just starting to play with this idea, not much POI shift.
Ex: From my 101st set at 29" and 71#
446 grain FMJ's with around 10.5% FOC at 294fps
401 grain Carbon Express Maxima Hunters with about 12% FOC at 301fps
426 grain Carbon " " " with about 15% FOC at 297fps
All had the same POI out to 60 yards, wierd.
This year I am planning on running no less than 16% probably around 19%, just need to buy another bow and get started, lol.

Another note; Is it me, or does everyone else that tries this and tells someone about it, have them try and talk you out of this? Except on here of course.
 
#42 ·
Higher FOC is best for broadheads

Hello,
I did similar tests and got the same favorable results with higher FOC. I used CX Maximas with 10.5 % FOC and 15% FOC. The 15% FOC always outperforemed the 10.5% FOC (accurracy) with a small difference in trajectory.
Problem is many folks have 100 grain BH's.
An easy way to do get higher FOC with the Maxima's is use an 8-32 x 3/4" set screw screwed into the insert from the back of the shaft. (you remove the nock and need someone to fabricate a 3/16" rod with the correct allen wrench on the end) You can get an extra 25 grains with that setup, more if the set screw is longer.

Works great and you get to use the 100 grain BH's you already have.

Thanks for the great test report.

oldbuck
 
#9 ·
I am getting ready to do it on my new Maxxis 31 with ACC 440 Prohunters.I ordered some 150 gr Magnus stinger buzzcut 4 blades and will be shooting 4" spin wings which should be a very forgiving arrow yielding about 19%-20% foc at 420 grains.

I think this will be a deer killing machine.:darkbeer:
 
#12 ·
This is what I achieved thus far:

Carbon Express Rebel Hunter 6075: 28" 589gr
Point: 125gr
Added weight: 100gr.
FOC: 17%
Speed: 212f/s at 60# (PSE Mojo)

This is what I am aiming for in the new year:

Total arrow weight: 650gr
FOC: 20% +
Arrow speed: preferably 250F/s or more.

Any suggestions on shaft/point combination I may try to achieve these specs?

The Grizly Sticks is an option, but no one stocks it in South Africa and the Ashby broad heads and German Kinetics are VERY expensive.

Quote:
Originally Posted by EnglishKev
I shoot just over 20%.
They tune well and fly even better.
I am currently building a couple of arrows to test the 'high FOC drops faster' theory.
So, two arrows, identical length, spine and weight, same fletching, one high FOC, one low FOC.
I will post the results over the weekend (weather permitting).

Kev
I would also be VERY interested in these results as this is a hotly debated topic over here in South Africa ...
 
#13 ·
I just finished reading through Dr Asby's latest reports and learnt about Ultra Extreme FOC arrows and their effectiveness.

These are arrows with a FOC of more than 30%.

Does enybody have an idea how one would go about to build such an arrow to be shot out of a bow of 65 - 75# draw weight? The arrow should weigh 650gr or more and travel at about 250f/s.
 
#20 ·
I also read an article by dr ashby who did a 30+ year study on big game penetration and arrow flight his results were impressive. And another study by richard combs who discusses more about long range arrow flight and wind effects his findings on accuracy and forgiveness are unignorable. I shoot about 13% now which is adequate Im sure, but who wants adequate?
 
#14 ·
My personal experience tells me high FOC is over-rated unless your hunting something very large. I played with tips between 85 and 125 grains last year and different spine arrows to match. I ended up with 85 grain Mugnus Stingers on GT 340 spined arrows with an FOC of around 9%. I'm no expert but have tuned alot of bows and I'm very, very picky as far as tuning goes. These shot exactly with FP and same group sizes at 60 yards and produced over 70 lbs Kinetic energy shooting over 300 fps. Way more than enough for Whitetails and speed as a bonus. Pass through (easily) on all three deer I've killed this year. I experiment every year so this year I'll try even more extreme FOC and I may learn something. But I have never had hunting arrows fly so well as this year at a sub10% FOC.
 
#18 ·
I've been shooting a set-up like that for 3+ years and loving the results. Many kills later & 1 hog going 400+ I have no complaints.
 
#15 ·
I have a 210gr Silverflame that I will be playing with this spring and summer. The only problem is that even at 210gr, the best I can get is 16% with my FMJ's and 18.2% with my TR Crush arrows. I also need a .300 spine arrow even with 100's or 125's, so I have no idea what the arrow spine ends up at with that 210gr head on the end.
 
#16 ·
... unless your hunting something very large
Not necessarily something large, but I am tired of passing up shots just because the animal was not presenting a good broad side or quatering away shot. I want something that will be able to go through fairly heavy bone on most of the antilope species in South Africa.

I do a fair bitof walk & stalk hunting and I don't want to go through all the effort to get within bow range and then have to pass up on a shot because the animal was not positioned perfectly ...
 
#17 ·
I've talked with Darrin Cooper "DD Bowhunting & ex-Head Engineer @ Hoyt" about this subject some and I know Coop really thinks it makes a difference...He told me the other day that the arrow he hunted with this year weighed in a tad over 500grs "I think he said like 507grs or so"...Anyway, Coop has played with high FOC's alot and he said he's found around 150grs of weight up front to be the sweet spot for him. In the past what he's done on his FMJ arrows is screw weights into his inserts and then run a 125gr head to get the weight...Now he's using the 50gr brass HIT inserts you can get to gain the extra weight. We were talking broadheads and vanes the other day and Coop always shoots either 3" or 4" vanes and various broadheads..I told him all the great flight I've had with 100gr Shuttle T-Locks and using Blazers and he said he was gonna play with some 2" Blazers on his 340 spine FMJ's with the 50gr brass inserts and a 100gr Shuttle T-Lock and see what he thought. I told him I've got Shuttle T's to fly well up at 330fps "X-Force" with Blazers so he said if that was the case he should get some great long range accuracy with them since his Alphamax 35 hunting rig isnt nearly that fast with his heavy arrows.
 
#21 ·
the highest I have been able to physically measure with Axis 300's is 17.9% using a 75 grain brass insert and a 150 grain head. The highest with Axis 400's is 18.6% using a 50 grain brass insert and a 150 grain head, but with those you'd have to use like a 50# bow. You can achieve 15.1 to 15.4% with the same set ups only with 100 grain heads. As far as price goes, I think Carbon Express Maxima Hunters with the built in weight forward is the way to go. I will try and keep everyone posted on my findings when I buy some on the 5th (payday, lol).
 
#27 ·
Ok guys,

Here are brief details of the first tests.
Arrows; GT expeditions 5575, 28'' from insert to centre of nock, 4'' helical feathers.
Arrow1; 100gr insert, 125gr tip, total weight 475.1gr, FOC 21.4%, yellow nock.
Arrow2; 15gr insert, 125gr tip, total weight 475.5gr, FOC 10.5%, white nock.

Test distances were shot out to 55 yards.
It would appear that FOC has little to do with drop.
As long as I did my part properly, there was very little difference in the vertical impacts of the two arrows.
I did notice, however, that the high FOC arrow seemed much more forgiving to shoot than the other.
I could get away with the odd slight form discrepancy and get a more accurate hit with it, also, the slight breeze that popped up every now and then seemed to have a greater effect on the low FOC arrow.
Penetration into the foam targets favoured the high FOC arrow as the distance increased.

Kev
 

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#30 ·
Thanks for the test,you proved to yourself and others what some of us already knew.Arrow weight is arrow weight,regardless of foc.As long as the foc is sufficient,the 2 should impact the same.The latter is the main reason I am trying it this coming year.I like all the forgiveness I can get.
 
#31 ·
Yep.
When I switched to carbons from ali, I wanted to keep the weight up.
My hunting buddy in Florida suggested the 100gr inserts (he is a traditional shooter) so I tried them and liked the way the arrows shot.
I have stuck with them ever since.
The Steelforce Premium 4 blade broadheads and the Woodsman 3 blade broadheads which I use come in 125gr weights, so totals 225gr.

Kev
 
#33 ·
If anyone decides to use Carbon Express Maxima Hunters, Gold Tip screw in weights fit inside the shaft for the back of the insert. I did go out and buy 2 of them (arrows) yesterday and did point/weight combos for 75, 85, 100, 125, and 150 grain tip with insert weights ranging from standard inserts, 20, 50, and 70 grain. I have them all written down. I was able to achieve up to 21% with the Maxima 250's (total weight of 491 grains) and up to 19.6% with Maxima 350's (526 grains total weight). From what I gathered from my tests you can achieve 16%+ fairly easily and be right around 455 to 476 grains. I currently have emails out to Easton, Carbon Express, and Gold Tip about just how much weight will be safe, hopefully hear back from them on Monday or so.
 
#34 ·
Alot of trad shooters set up arrows with EFOC for better penetration and flight for years.

I have my arrows set with efoc on my trad tackle and like the results. I am shooting 200gr tip that give me 29% FOC. The idea to get EFOC is to shoot a slightly stiffer arrow and use heavier tips.
 
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