FOC thoughts please!

bob.bowers

Well Known Rokslider
Joined
Jun 2, 2015
Messages
121
Location
Roanoke, VA
I have always built a fairly heavy arrow for elk, but never more than 600 grains. I don't like to be less than 525 grains as my personal threshold, and don't judge anyone else, these weights are just for me personally.

I've also never put a ton of thought into FOC other than I wanted to shoot for 10+ percent and have normally ended up around 11.5-12% on average.

This year I thought I'd get crazy so I built a set of Victory RIP HV 250 spine shafts with a 72 grain Gold Tip stainless halfout with a 50 and 20 grain back weight for a total insert weight of 142, 125 grain tip or broadhead, Firenocks and three max helical AAE Max Stealth vanes. TAW of 550. FOC is 18-19% with this shaft.

These things fly awesome, but not a great deal better than my 11.7% GT Kinetic 200's. I spend a lot of time tuning my bow so it hits factory specs and shoots bare shaft as well as the fletched shafts. I nock tune each arrow, then fletch to that mark. I spend a great deal of time trying to make the most accurate, best setup I can so the margin for error is smaller.

My thoughts on the higher FOC arrows was more along the lines of the physics involved. With the fulcrum being more towards the tip of the arrow, it takes less "effort" or "energy" for the vanes to do their job of correcting what the broadhead is imparting to the shaft. Also, on impact, with a larger amount of the TAW being up front, there is less energy bleed in the shaft bending on impact, thus assisting in greater penetration.

This is the first set of shafts that I've built with this kind of FOC. I really like them and think they are going to do a great job on elk this fall. But I'm also not crazy about FOC, and very much like my Kintetics and they are very proven on a lot of different game.

But how do you feel about FOC for you personally, and what are your reasons behind your decision either way?
 

Mighty Mouse

Well Known Rokslider
Joined
Jun 21, 2019
Messages
1,704
Location
Oklahoma
I agree that a high FOC arrow should require less fletching and should exhibit less shaft flex on impact, but I'm not sure how much those theoretical benefits actually help in practice. I worry about the ability of thin-walled lightweight shafts to handle hard/angled impacts without breaking, so I stick with medium-to-high gpi shafts even though it sacrifices some FOC. For the animals I hunt (whitetail and elk), I want a durable arrow around 500 gr TAW and let FOC fall where it may...currently it's falling around 14% (300 spine 5mm Axis cut to 27.5" with 150 gr head, 25 gr insert, 4 Heat vanes, no wrap, unlighted nock).
 

Bump79

Well Known Rokslider
Joined
Oct 5, 2020
Messages
417
I personally like 15%-18%. Seems like my flight improves but after that things get weird quick. I don't believe in increasing FOC just for FOCs sake, I build a durable component and broadhead and it typically gets me in the ballpark on my light shafts.

I actually don't like getting over 175 (maybe 200) total up front because I like being able to use glue in tips for practice with my X-Impacts or Element Storms. Cheaper to sling around.
 

Billy Goat

Well Known Memester
Joined
May 6, 2018
Messages
7,197
Location
Shenandoah Valley

To give a better answer.

I think weight up front is important, but personally I don't think it's a percentage thing. Just need some mass up there, doesn't matter if it's 27" or 31" behind it.


Plenty of top shooters are way too accurate with arrows that hafta be 7% or less, and they don't change things much when they go to broadheads.

Generally I follow Eastons recommendations, they have spent way more time on it than I. Minimum 7% for target, Minimum 10% for hunting. Generally a hunting shaft 10-15%.
 

MattB

Well Known Rokslider
Joined
Sep 29, 2012
Messages
4,284
Ignore FOC would be my best advice. Guys killed thousands of animals with bow and arrow before it even became a thing.

Sometimes the internet is a bad thing. Spend your time shooting rather than mentally masturbating.
 

LONE HUNTER

Well Known Rokslider
Joined
Feb 25, 2018
Messages
211
No, I don't care about FOC anymore. There is so much shit to check and ensure is good on a bow along with spending time tuning and shooting that I don't have time to split hairs about that kind of stuff. Easton axis 300 spine, normal inserts, 100grain broadheads. Unless they stop making those arrows I am not switching again.
 

WMag338

Well Known Rokslider
Joined
Apr 11, 2020
Messages
248
Location
SC
I am by no means an archery expert. I am shooting axis 260 spines, 15gr insert, IW collar, 100gr IW head. TAW is 512. With my 29.5" shaft & 29.5" draw, I am getting 11-12% FOC +/-. Arrow speed is 272 fps. Had complete pass throughs on elk & moose. My IW broadheads will cut the nocks off my field points at 100 yards if I do my part.

I can't ask anymore from my setup. Not super high FOC, not super heavy TAW. It just works for me.
 

406unltd

Well Known Rokslider
Joined
Jul 6, 2018
Messages
665
I’ve used anywhere from 10 ish to 19.5%. Had success with both. Had a couple less than ideal outcomes on the 10% side of things. This was indicative of the lack of overall weight/ poi, and not foc. I sit at 15-15.5% right now and it’s a happy medium.
 

Arctic Hunter

Well Known Rokslider
Joined
Aug 6, 2016
Messages
448
I used to geek out on it. It probably helped with my recurves. But with a compound it seemed to cause more issues than it was worth. I seem to get better arrow flight when I don’t get too crazy with it.
 
OP
bob.bowers

bob.bowers

Well Known Rokslider
Joined
Jun 2, 2015
Messages
121
Location
Roanoke, VA
Very interesting comments. I certainly don't "mentally masturbate" to this, but like anything, it is worth researching and experimenting with to see if one thing works better than another. Like I said in my original post, my 11.7% FOC shafts are shooting about as perfect as any shaft I've ever shot, so why fool with another? Maybe because I'm always tinkering and in so doing, I have found much better things, and some did not work out as I thought. Thus my questions to you guys on your experiences.

I don't think super high FOC is always a good thing. I think getting the shaft tuned by nock tuning is the most important thing for consistent arrow flight from one shaft to the next. I also think for hunting purposes, you need the shaft rotating at as high a rate of speed as you can get it, "parachuting" effect be damned. I don't see any of that with the shafts I have that are spinning at a high rate of speed. I will say when you get the shaft spinning super fast, it WILL penetrate further/deeper into the target/animal.

I don't geek out about high FOC, but it has been fun to play with it so far. But the jury is still out as far as if the high FOC arrows will make it into my quiver or my 11.7% FOC shafts. It will certainly boil down to which flys the best and the ones I have the most confidence in overall.

Thanks for everyone's input thus far.
 

Zac

Well Known Rokslider
Joined
Dec 1, 2018
Messages
2,004
Location
UT
I am a huge believer in high FOC. I have done lots of expiermenting and found that if you are over 27% you don't even need fletching at all. This led me to even more expiermenting. I have found that at 30 and above %, there is actually no need for a nock. I just score a small mark in the back of the shaft with a hacksaw and she's good to go.
 

nuts&bolts

Junior Member
Joined
Aug 8, 2022
Messages
14
Super high FOC...30% FOC and higher even. What distance did you shoot?
I did super heavy FOC arrows, but only tested to 20 yards.
 

dj1975232

Member
Joined
Aug 9, 2022
Messages
71
I’ve tried the very high FOC arrows and although they work I’ve settled in to above average FOC usually coming in around 550 grains @ +/- 15%.
 

camelcluch

Well Known Rokslider
Joined
Mar 4, 2014
Messages
1,478
I have had 8% to 19%. Good arrow flight with all. However, I do find a reasonable foc drives the arrow to the spot. I try to get 15% but it’s not a deal breaker. Arrow flight is what I look at now but I do try to keep a good medium.
 

nphunter

Well Known Rokslider
Joined
Jul 27, 2016
Messages
1,209
Location
Oregon
I'm shooting over 20% FOC just to get to 500gr with my RIP TKO's, they need just as much fletching as my lower FOC arrows have in the past and don't fly any better at a longer distances. The best flying arrows I've ever built were 4mm, A/C Injexions that were on the very bottom end of my spine stiffness, all the calculators and charts said I was under spined, they flew excellent at long range, high speeds with fixed heads.

I do however like the thought of most of my weight at the front of my arrow and having a very durable arrow, I am shooting 100gr SS HIT's, 25gr SS Collars and 100gr mechanical heads. My thought is that with the majority of my weight on the front of the shaft I should get less deflection and the majority of the mass of the arrow will be inside of the animal very quickly after hitting it. My thought is that by having the majority of the weight inside even if the animal moves it should help to pull the rest of the arrow thought upping the likely hood of a pass through. Maybe I'm thinking about this wrong but it makes sense in my head and I've had good luck with killing animals with high FOC arrows weighing 500gr on the money with big mechanical, they are bad medicine to everything they have hit, elk, deer, and antelope.
 
Top