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Main Boards => PowWow => Topic started by: Wudstix on November 04, 2020, 07:15:24 AM

Title: How much FOC is too much?
Post by: Wudstix on November 04, 2020, 07:15:24 AM
Was wondering if there is such a thing as too much FOC?  Right now have a Beman 400 29" with Big Jim(VPA) 300 grain and 100 grain brass insert running 28.17%.  Just fiddling with carbons and may use on hogs.
:campfire:
Title: Re: How much FOC is too much?
Post by: smoke on November 04, 2020, 07:59:25 AM
I think it becomes too much only when your spine becomes too weak and your arrow no longer flies true. 
Title: Re: How much FOC is too much?
Post by: bowmaster12 on November 04, 2020, 09:01:14 AM
As much as you can get and maintain good arrow flight and you or ok witb the trajectory of the arrow
Title: Re: How much FOC is too much?
Post by: blacktailbob on November 04, 2020, 01:17:59 PM
Maybe a little.
Title: Re: How much FOC is too much?
Post by: Pine on November 04, 2020, 01:46:18 PM
There is such a thing as diminishing returns.
A few years ago I was shooting at the archery range with my 60# recurve with an arrow that weighed 610gr.
A guy had me try one of his arrows that weighed a little over 1000gr. and at 20 yards it hit about 4" lower and bounced off the backstop.
My arrows were penetrating about 6" so where's the advantage of an extra heavy arrow?
Title: Re: How much FOC is too much?
Post by: Wudstix on November 04, 2020, 01:52:44 PM
Just tinkering with a couple carbons before I trade them.  I'll get the woodies flying well.  Perhaps use the odd one of the carbons on hogs.  Really hate to break a woody on a feral.
:campfire: :archer2:
Title: Re: How much FOC is too much?
Post by: ozy clint on November 04, 2020, 02:15:48 PM
only disadvantage I see is that in a cross wind they fly 'sideways', with the fletching not following the path of the point. this somewhat negates the penetration benefits.
Title: Re: How much FOC is too much?
Post by: Sam McMichael on November 04, 2020, 04:03:28 PM
I agree with bowmaster12.  Good arrow flight and trajectory are the essence of great performance, and when this is combined with high FOC good results are quite likely.
Title: Re: How much FOC is too much?
Post by: Sojurn on November 04, 2020, 05:09:30 PM
My experience mirrors ozy's.  To much foc and they fly sideways in a crosswind.  I keep my foc in the 18 to 20% range, and worry way more about arrow flight.
Title: Re: How much FOC is too much?
Post by: Wudstix on November 04, 2020, 07:27:11 PM
I'll keep fiddling after I get my wood arrows flying well with Snuffer 160 grain heads.  Right now at 625 grains and 9.4 gpp.  Hit right on spot, if I do my part.
:campfire: :archer2:
Title: Re: How much FOC is too much?
Post by: David Phillips on November 04, 2020, 08:52:35 PM
The guy from the Traditional Wilderness podcast has a video of him shooting the big 1 1/2" mangus broadheads without fletching, bare shaft. I think he said he's shooting 30% FOC. The shaft follows the weight. You can have high FOC without an overweighted total arrow weight, the two are not synonymous. The whole point of FOC is most of the weight forward.
Title: Re: How much FOC is too much?
Post by: woodchucker on November 04, 2020, 09:26:43 PM
I only shoot wood arrows, so all this FOC stuff kinda stumps me??

I use the 1/3 balance test. I set my finished arrow on the table, and slowly push the point end off.
I want the "balance" point to be about 1/3 back on the shaft from the BOP.

Works for me... My arrows fly just fine :archer:
Title: Re: How much FOC is too much?
Post by: Wudstix on November 04, 2020, 10:11:33 PM
David;
With the set-up mentioned 57% of total weight is in the front @3".  They flew great at close range after I get my wood arrows tuned up I'll go back a mess with the carbons a bit at 15 yards plus.  Wood takes priority.
:campfire: :archer2:
Title: Re: How much FOC is too much?
Post by: David Phillips on November 05, 2020, 10:56:05 AM
I shoot wood arrows most of the time myself, but the durability of carbon cannot be denied. Hogs especially are hard on wood shafts. I've shot a lot of hogs and everyone I've shot with a wood shaft was broken. Carbon has its place and I carry a couple in the back quiver for hogs while deer hunting. The EFOC extreme forward of center does help with wind planing and penetration. There will be a different trajectory than a wood shaft with the weight more evenly distributed. Getting 25-30% EFOC would be near impossible with wood arrows so a lot of people that only shoot wood don't understand it. Dr. Ashby did enough testing on FOC EFOC heavy arrows etc. to prove the point. You'll notice no one has disproven his reports or proved a POC arrow with 125 grain Bear razorhead out penetrates a EFOC heavy carbon arrow and they never will.
Title: Re: How much FOC is too much?
Post by: old_goat2 on November 05, 2020, 11:49:49 AM
Quote from: ozy clint on November 04, 2020, 02:15:48 PM
only disadvantage I see is that in a cross wind they fly 'sideways', with the fletching not following the path of the point. this somewhat negates the penetration benefits.
Did you reduce the size of your feathers in relation to how much you increased FOC? This will make a big difference in how they handle a crosswind. Increasing FOC increases the lever arm length the feathers act upon. I don't have any more tail wiggle with my high FOC arrows than I do with my more balanced arrows and they seem to hold the line better
Title: Re: How much FOC is too much?
Post by: woodchucker on November 05, 2020, 12:55:35 PM
Thank you for putting it in "dummy terms" David!!! :notworthy:

Tyler builds all of our arrows, so breaking or loosing them doesn't hurt so bad!! LOL :thumbsup:
I'm gonna sit this one out..... :coffee:
Title: Re: How much FOC is too much?
Post by: ozy clint on November 05, 2020, 02:06:42 PM
old_goat2- i use 4x4" parabolic feathers.
Title: Re: How much FOC is too much?
Post by: Wudstix on November 05, 2020, 06:12:48 PM
Finished tuning a set of Big Jim wood arrows I got in a trade.  FOC on woodies is right at 18% and at 15 yards hitting the spot when I do my part.  625 grain arrow weight with @ 9.4 gpp.  Think this will hunt for me.  May drag a couple carbon sticks for hogs. 

Title: Re: How much FOC is too much?
Post by: old_goat2 on November 06, 2020, 10:35:33 AM
Quote from: ozy clint on November 05, 2020, 02:06:42 PM
old_goat2- i use 4x4" parabolic feathers.
. That's way way too much feather for high FOC, perfect for balanced foc, it's no wonder you seen the fishtailing.
Title: Re: How much FOC is too much?
Post by: McDave on November 06, 2020, 10:57:11 AM
Interesting, I never knew that some of the speed loss from EFOC, or to be more precise the higher gpp that results, could be offset by smaller feathers resulting in lower wind resistance.
Title: Re: How much FOC is too much?
Post by: bowmaster12 on November 06, 2020, 12:55:00 PM
In reading about high foc Dr. Ashby actually reduces fletching size just until the arrow slightly loses control.  Then adds what he calls a turbulator  just infront of the fletch.  This restablizes the arrow allowing for the minimum amount of fletching and weight at the back of the arrow.
Title: Re: How much FOC is too much?
Post by: ozy clint on November 06, 2020, 04:22:15 PM
Quote from: old_goat2 on November 06, 2020, 10:35:33 AM
Quote from: ozy clint on November 05, 2020, 02:06:42 PM
old_goat2- i use 4x4" parabolic feathers.
. That's way way too much feather for high FOC, perfect for balanced foc, it's no wonder you seen the fishtailing.

they don't fishtail, they fly slightly sideways in a stiff cross wind. this effect maybe tolerated for the overstabilization they provide in hunting situations of poor release, wet feathers etc
Title: Re: How much FOC is too much?
Post by: old_goat2 on November 06, 2020, 09:32:17 PM
Quote from: McDave on November 06, 2020, 10:57:11 AM
Interesting, I never knew that some of the speed loss from EFOC, or to be more precise the higher gpp that results, could be offset by smaller feathers resulting in lower wind resistance.
first set of Efoc arrows I tuned in, point on distance stayed the same even though the arrows were significantly heavier
Title: Re: How much FOC is too much?
Post by: Hud on November 06, 2020, 10:30:58 PM
I believe Dr Ashby determined that 29% FOC was Extreme.  I am not convinced that using a high FOC is beneficial for typical game.
Title: Re: How much FOC is too much?
Post by: flyonline on November 07, 2020, 03:43:29 AM
Quote from: David Phillips on November 05, 2020, 10:56:05 AM
Dr. Ashby did enough testing on FOC EFOC heavy arrows etc. to prove the point.

I thought that he "proved" that structural integrity and arrow flight were MORE important than FOC, yet somehow this doesn't seem to come up often in discussion on FOC %'s - especially by those touting high %'s  :dunno:

Nock high that can't be tuned out seems to be another problem that often comes up with higher FOC %'s as well.
Title: Re: How much FOC is too much?
Post by: old_goat2 on November 07, 2020, 05:58:49 AM
Quote from: flyonline on November 07, 2020, 03:43:29 AM
Quote from: David Phillips on November 05, 2020, 10:56:05 AM
Dr. Ashby did enough testing on FOC EFOC heavy arrows etc. to prove the point.

I thought that he "proved" that structural integrity and arrow flight were MORE important than FOC, yet somehow this doesn't seem to come up often in discussion on FOC %'s - especially by those touting high %'s  :dunno:

Nock high that can't be tuned out seems to be another problem that often comes up with higher FOC %'s as well.

I didn't have either of those problems, have seen nock high that won't tune out with normal foc arrows. Not trying to get on the you have to shoot high FOC arrows train here, but if done properly the arrows fly amazing, but it has to be done properly and you have to go the whole nine yards with it not just throw a bunch of weight on an arrow
Title: Re: How much FOC is too much?
Post by: Wudstix on November 07, 2020, 08:01:40 AM
Good to know should I need to back down in bow weight.
:campfire: :archer2:
Title: Re: How much FOC is too much?
Post by: McDave on November 07, 2020, 08:20:23 AM
Quote from: old_goat2 on November 06, 2020, 09:32:17 PM
Quote from: McDave on November 06, 2020, 10:57:11 AM
Interesting, I never knew that some of the speed loss from EFOC, or to be more precise the higher gpp that results, could be offset by smaller feathers resulting in lower wind resistance.
first set of Efoc arrows I tuned in, point on distance stayed the same even though the arrows were significantly heavier

If everything else stays the same: bow, anchor, draw length, shooting form, etc., point on must decrease when arrow weight increases.  If, for some reason, your point on is closer than usual, for example, if you are using a fixed crawl or high anchor point, you won't see as much change as you would with a 40-50 yard point on, but the point on will still change.  So what else changed?
Title: Re: How much FOC is too much?
Post by: David Phillips on November 07, 2020, 10:17:00 AM
Quote from: flyonline on November 07, 2020, 03:43:29 AM
Quote from: David Phillips on November 05, 2020, 10:56:05 AM
Dr. Ashby did enough testing on FOC EFOC heavy arrows etc. to prove the point.

I thought that he "proved" that structural integrity and arrow flight were MORE important than FOC, yet somehow this doesn't seem to come up often in discussion on FOC %'s - especially by those touting high %'s  :dunno:

Nock high that can't be tuned out seems to be another problem that often comes up with higher FOC %'s as well.
If you read all the work he's published you'll find he proved several things. You shouldn't need to be told arrow flight and structural integrity is important. You can shoot an arrow with high or extremely high FOC that wobbles and hits sideways if you want to, or you can take the time to do it right. You can also shoot wood and only wood and disbelieve the FOC EFOC flight and penetration advantages but it doesn't change the results.
Title: Re: How much FOC is too much?
Post by: Friend on November 08, 2020, 01:50:18 PM
Have found no issues with Ultra EFoc shafts.

Have shot complete 3D rounds with a Ultra EFOC bare shaft and have recorded an 8.0 average per target. The pressure on the feathers is greatly increased when in the upper thresholds of FOC.

One simple test is to shoot an arrow with 4" feathers at 40 yards and then should another arrow of the same identical specs with the exception of utilizing 5" feathers. There will be a noticeable drop at impact.



Title: Re: How much FOC is too much?
Post by: Wudstix on November 09, 2020, 01:33:13 PM
All good info.  I'm not real familiar with carbons, having ever hunted or shot 3-D with them.  Plenty of room to experiment it seems.
:campfire: :archer2: :coffee: