Anyone shooting very high FOC?

[Beendare]

I'm curious with all of the Ashby followers, How many guys are shooting his recommended 30% plus FOC?

I asked this on the big Archery site and it got lots of views and responses................very few actually shooting an FOC that high. [one actually]

I'm curious if there is anyone shooting an Adult weight bow [60#, 70#] and an average arrow length- 28", 29" with the very high 30% FOC. If so please post your specs....much appreciated.

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[Marble]

Uh... no. I'll just stick a decently heavy arrow at a good speed that shoots lights out.

 

[Zac]

I was at 20 percent before I started running Firenocks, now I think around 18.8. Have a Victory Elite Vap 250, 28.5 C to C. 20 grain aluminum collar. 230 grain Valkyrie Jagger, 4 fletch AAE Pro Max and a Firenock. 570 groans doing 270 fps from Mathews VXR 70 lbs, 31 inch draw with 80 percent mods.

 

[Marble]

I was at 20 percent before I started running Firenocks, now I think around 18.8. Have a Victory Elite Vap 250, 28.5 C to C. 20 grain aluminum collar. 230 grain Valkyrie Jagger, 4 fletch AAE Pro Max and a Firenock. 570 groans doing 270 fps from Mathews VXR 70 lbs, 31 inch draw with 80 percent mods.

That sounds like a killer set up right there.

 

[bjfoxhoven]

I’ve been shooting around 17-18. Most traditional guys I shoot with usually don’t know where they are % wise, but from feeling their stuff they too are usually upper teens to low 20s on the higher end. Have not seen one shoot in the 30% range

 

[Mighty Mouse]

This Ashby-based source defines 19-30% as "extreme" FOC and >30% as "ultra-extreme":

https://www.ashbybowhunting.org/s/2019-Terminal-Arrow-Performance-Update.pdf

I generally agree with Ashby's recommendations, but I believe he and his acolytes state their conclusions with excessive numerical certainty (e.g., 650 grains and 19% [or 30%] FOC is the ultra-penetrating/bone-breaking threshold). I also think Ashby's trad bow test results probably don't correlate 1:1 to modern compound bows. Also, shaft stiffness would severely limit your options if trying to build a 30% FOC arrow for a mid-high draw weight compound.

I do believe arrow weight has a greater influence on penetration than speed, and I build my hunting arrows accordingly. Since most weight adders go on the front, my FOC comes out pretty high too. My current hunting arrows (for a 70# compound) weigh 630 gr with 20% FOC:
GrizzlyStik Momentum 240 at 27.25" C2C = 317 gr
Cutthroat broadhead = 150 gr
In/outsert = 70 gr
Stackable brass weight = 50 gr
Firenock = 25 gr
Three 2" Blazer vanes = 18 gr

 

[Beendare]

I agree with your post Mighty...and I don't want this to turn an Ashby argument.

I do agree with arrow weight being a big penetration factor...and bowhunters knew this long before Ashby.

I'm focusing on the very high 30% plus FOC claims. ...seeing who is actually doing it.

I've personally tried building an arrow with 30% FOC before my Australian hunt for Buff. My 29" arrow got dangerously squirrely when I got up to 27% and all that tip weight...so I backed off the tip weight and got a really good flying arrow.

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[Brendan]

I just ran some theoretical numbers through SFAX starting with my current setup. If I switched to a Black Eagle Rampage 150 with a total weight of 900 grains up front, 1,382 Total Arrow Weight, 172 FPS puts me at 30% FOC according to the calculator with adequate spine.

FWIW, I'm running a 518 grain Easton Axis 300 at close to 280 fps, haven't given any actual thought to playing with that setup.

 

[Mighty Mouse]

My 29" arrow got dangerously squirrely when I got up to 27% and all that tip weight

Do you think you were still adequately spined at 27% FOC? FWIW, Ashby does place arrow flight ahead of FOC in his ranking of penetration enhancing factors.

One of these days I may play around with my GrizzlyStiks and see how far I can push FOC and still get a good paper tune. A 200 gr head, an additional 50 gr stackable weight, and swapping the Firenock for a standard nock would get me to 710 gr and around 25% FOC.

 

[ozyclint]

i have one setup that is at 34.3% FOC. 300gr tuffhead, 335gr custom glue in/glue on adapter, 6 1/8" 2020 aluminium footing, 400 spine black axis shaft, 4x4" parabolic feathers. total arrow mass is 1005gr. 70# border black douglas recurve.
it's my waterbuff arrow.

 

[ozyclint]

i do believe there is a practical limit though for hunting in real world conditions. i have noticed that high FOC arrows are more effected by crosswind. they might drift less but they tend to fly more sideways in moderate to high crosswind because the wind is more easily able to act on the longer lever of the rear of arrow to balance point. the same as a wind vane where the center of drag is far behind the pivot point. in such conditions this negates the benefits of high FOC in terms of penetration. to what degree, i'm not sure.

 

[Billy Goat]

How many actually measure their foc versus what a program says?

I know when I have tried the gt program it always has me lower than when I actually measured it.

I do exclude point length. But it's still off even if I include it. I generally measure it on all my arrows just to satisfy curiousity. But I don't really build around it.

 

[Mighty Mouse]

How many actually measure their foc versus what a program says?

I know when I have tried the gt program it always has me lower than when I actually measured it.

I do exclude point length. But it's still off even if I include it. I generally measure it on all my arrows just to satisfy curiousity. But I don't really build around it.

I also measure (excluding point length) out of curiosity and have found the GT calculation to run a bit lower (0.5-1.0%) than measured FOC.

 

[D.Rose]

What is everyones reasoning for using such high FOC? Do you guys ever run in to any tuning issues with such crazy point weight?

 

[rekkr870]

What is everyones reasoning for using such high FOC? Do you guys ever run in to any tuning issues with such crazy point weight?

I find that my arrows are easier to tune with high FOC and high point weight.

Sent from my SM-N960U using Tapatalk

 

[Brendan]

i do believe there is a practical limit though for hunting in real world conditions. i have noticed that high FOC arrows are more effected by crosswind. they might drift less but they tend to fly more sideways in moderate to high crosswind because the wind is more easily able to act on the longer lever of the rear of arrow to balance point. the same as a wind vane where the center of drag is far behind the pivot point. in such conditions this negates the benefits of high FOC in terms of penetration. to what degree, i'm not sure.

This is a big issue with high FOC if you get into a crosswind scenario. Rear of the arrow kicks out, arrow impacts off-axis with shitty arrow flight, kills penetration. With a lower FOC arrow, the arrow stays truer along its' axis, and although it will drift more (you need to compensate) you'll get better arrow flight and thus penetration in that scenario.

Can't remember where I heard a discussion about this, podcast probably.

 

[Beendare]

Clint, Have you bare shaft tested that 1,000 gr high FOC arrow?

i do believe there is a practical limit though for hunting in real world conditions. i have noticed that high FOC arrows are more effected by crosswind. they might drift less but they tend to fly more sideways in moderate to high crosswind because the wind is more easily able to act on the longer lever of the rear of arrow to balance point. the same as a wind vane where the center of drag is far behind the pivot point. in such conditions this negates the benefits of high FOC in terms of penetration. to what degree, i'm not sure.

Agreed. Our Club range has a strong cross wind and when shooting that very high FOC arrow I could see the tail wagging. In fact in a 20 mph wind...it looked like the tail was 10 degrees off to the side.

Could it be that pushing the balance point too far forward [very high FOC] destabilizes the arrow? Yes, no doubt. It seems Easton knew this decades ago when coming up with their FOC recommendations.

All of the folks pushing this very high FOC talk always about an arrow in flight, which is only 1/2 of the equation- never about wind and never the destabilizing effect all that tip weight has on the launch. The launch is where our accuracy originates. Plus; Its a physical law; Equal and opposite reaction...any advantage tip weight has on the back end is counteracted at launch. Reasonable FOC gives us this balance we need.

One thing we know for a fact; Even a tiny bit of poor arrow flight KILLS penetration.

Perfect arrow flight should be numero uno on any list of arrow factors.

In the real world we see that low energy setups from very light bows can shoot through deer...but then untuned compound bows at 60# and 70# have problems with penetration. No doubt, much of those problems can be attributed to poor arrow flight.

Bottom line; Ashby reiterated what we have known about arrows since the 1200's; Heavy arrow performs better and we want a strong BH. His other stuff on Massive FOC is not only questionable...its just noise.

Edited for clarity....


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[VTJ]

While I understand the whole Idea behind the Ashby crap, I dont buy into it ... I am not chasing water/cape buffalo... I have always been in the 9.5-12% FOC range (10% right now) and with proper tuning (Bare Shaft) and if needed BH tuning I get fantastic BH flight ... my arrows both FP's/BH's stack at 40/50yds ... Ive never seen the need, nor do I have the want to go heavier with FOC or arrow weight, not for deer, hogs or antelope, I'll stay in the 400-430 gr range thank you very much and I'll continue to kill all the critters I intend.. ... I'm at 410 grs now and 297fps/30" draw/63-64lbs ... the new Elite Ritual 33 is super quiet and very accurate .. I'd only go heavier for elk and that would be to a 450-475 gr range ... todays bows produce more than enough energy/momentum for any critter in North America ... just be sure your tuned as well as you can, get proper arrow flight, dont get carried away by the heavy arrow/foc bullcrap and stay in the 10-15% foc range and medium weight arrows for the critter you are after so you get a tad of speed and enjoy ..

 

[ozyclint]

Clint, Have you bare shaft tested that 1,000 gr high FOC arrow?
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no. i don't bareshaft tune. it flys awesome though

 

[Beendare]

FWIW, Informal Statistics;

I posted this same question though worded slightly different "Who shoots 30% FOC?" on multiple sites.

Well over 1,000 views....many responses [but no where near 1,000.]

Out of all that, 3 guys actually shooting FOC of 30% including Clint above. All were very heavy arrows.

A lot of guys with good success in the 20% range. A few guys tried getting to 30% like myself but didn't have good arrow flight.

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