High FOC.. help me understand..

[Rob DiStefano]

Originally posted by DanielB89:
... What do you do for tuning purposes?  As any archer who is relatively "new to the game", you learn from those who will teach you, research, topics like this, etc.  ....

for me, simply put, i just let the completed arrow do the talking.  i fly each one maybe a dozen times and see what's happening.  if i can't correct a bad flying arrow, and i know for SURE it ain't me, i'll video the shooting.  seeing what you've done after the fact can be both sobering and humbling.  i've even gotten into videoing my rifle shooting, flintlocks and big bores.  when yer concentrating on the spot, as we all should, how yer bowstring fingers work and your holding and aiming form may very well be not what yer brain is thinking.  this video thing has really helped me with long range .45-70 shooting, as well as flinging arrows.

i can get most arrows to bare shaft well.  thing is, since i don't shoot bare shafts for game or targets, so i'd rather skip that step, fletch up, point up, see how they fly.  i pretty much know what SHOULD work before they even git on the bowstring, so it'd be rare to build an arrow and have it fly and land like krap.  but that can happen to me, and has ... but very rarely.  

there are dayze that i shouldn't pull string, and when i do, i know to stop and try some other day.  

i don't have, nor need, many bows, just three longbows that range from around 38# to about 53# at a draw of 29" to the front of the bow shelf.  when i build some arrows i'll shoote 'em outta all of 'em, get their opinion of what i just fed 'em and sorta take it from there.  they all will work one way or another.  the only thing i demand is at least 10gpp arrow weight, and will go upwards of 12-13 gpp.  

with carbons, i tune with the point weight, and a .500 spine works well for ME within my draw length and bow holding weights.  i hot glue points to adapters and can change out either.  sometimes, if i need a LOT of front end weight, i use a brass ferrule instead of the much lighter alum.  i keep spreadsheet charts of all my arrows and bows, all the pertinent data of what works.  

woodies are tougher, and when i have a group to build i'll bare shaft a few to see what i'm dealing with and take it from there.  sometimes, not often, with woodie arrows i need to make 'em a bit longer in length.  

in essence, there are things you learn to do, but there are no cut 'n' dry absolute formulas for arrow tuning that will work with everyone.  it's like shaft selection software - might look good on the screen, but reality is the judge and jury.  i don't like shaft software either.

i can't stress enuf how good a heavy arrow is in terms of ease of tune, stability in flight especially when yer release kinda sucks, how it quiets the bow string because it demands to eat the larger share of the transmission (bowstring) energy.  

no matter what the foc/lmnop, a goodly heavy arrow is like comparing getting yerself hit at 30mph by a car or a freight train - one requires a stretcher, the other a wide shovel scraper.     :eek:    

dang, i wrote a book and probably didn't say much worth a hoot!   :D

[JimB]

"dang, i wrote a book and probably didn't say much worth a hoot!"

Sorry Rob,I have to disagree.You said a lot and it's all pertinent.

[DanielB89]

Rob, I will agree on the book part!  as for the other part, I will have to see how that goes for me! lol.

Thanks for helping this post turn out well.  I will bring it back up in a few days when I figure out the exact set up that works for me.  


Rob,
have you ever shot/owned a black widow?

[Rob DiStefano]

Originally posted by DanielB89:
 ... Rob,
have you ever shot/owned a black widow?

shot lots, never owned.

[overbo]

Shot MA's for years ranging from 53lbs to 78lbs. They always required a stiffer spine arrow when comparing to others of the same draw weight.

[DanielB89]

Originally posted by Rob DiStefano:
 

Originally posted by DanielB89:
 ... Rob,
have you ever shot/owned a black widow?

shot lots, never owned. [/b]

That is why I asked.  I have never heard of one that didn't require a heavier spine that the same bow of a different brand.  

I have a friend who has a #50 widow.  He shoots HEXX .330's out of his with 250 grains up front.  

Kris, who also replied that he shoot a .350 with 500 grains up front, which is crazy to me.  I would have to shoot a .050 spine to shoot 500 grains up front.

[DanielB89]

Originally posted by overbo:
Shot MA's for years ranging from 53lbs to 78lbs. They always required a stiffer spine arrow when comparing to others of the same draw weight.

I agree.  I am shooting a MAIII that is #53@28.

[overbo]

MA's are cut a bit more past center than most others. There for the reason they shoot a stiffer spine arrow.

[DanielB89]

Originally posted by overbo:
MA's are cut a bit more past center than most others. There for the reason they shoot a stiffer spine arrow.

I had no idea! Do you know what they are cut to?

[Rob DiStefano]

Originally posted by DanielB89:
 

Originally posted by overbo:
MA's are cut a bit more past center than most others. There for the reason they shoot a stiffer spine arrow.

I had no idea! Do you know what they are cut to? [/b]

for any trad bow, it's relatively easy to check the arrow plate offset by checking the limb centers.

[overbo]

I want to say 3/16?? but could be wrong

[Flying Dutchman]

Yup, BW recurves are cut 3/16 past centre, which explaines why you can shoot them with stiffer spines.

[Flying Dutchman]

BTW,

Here you have a spine conversion table for a better understanding:

15-35 or 0.600" becomes: 26/0.6 x 1.2115 = 52.5 lbs
35-55 or 0.500" becomes: 26/0.5 x 1.2115 = 63 lbs
55-75 or 0.400" becomes: 26/0.4 x 1.2115 = 78 lbs
75-95 or 0.300" becomes: 26/0.3 x 1.2115 = 105 lbs


I am all the way with Rob! Looking at this figures, it is not so hard to understand that for most 45 to 55 lbs bows, a.500 or even an.600 spine (when shortened a little) would do fine.... Especially when you consider that carbon recovers much quicker from the paradox.

However, most carbon shafts wont go over the 8 GPI, resulting in a very low arrow weight, like 350 to 450 grains, if you would use a front weight of 100 to 150 grains. For a 50 lbs bow that would mean 7.5 to 9 GPP.

So what you do is go heigher in spine by shortening the shaft or taking a higher spine value and add front weight to get the arrow tuned and get more mass...

So what you really do is over-spining yourself and then correcting it with more front weight in order to get more weight.        

And that is how EFOC is born  

If you don't want EFOC, then simply take a lower spined shaft and put something in it. I had great results with weat-eater line.

My five cents...

[DanielB89]

I got my 2 arrows in yesterday.  One was a full length .350 and the other a full length.  I added my 100 grain insert and 175 grain point.  

I shot the .350 first.  The first shot the arrow was almost sideways in the air, I wanted to make sure it wasn't me, so I shot it a few more times with the same results.  So I took my 100 grain insert out and put it in the .300 spine.  

I was shooting about 3 to 4 shots before i trimmed the arrow any.  Every shot was weak, trimmed 1/2" off.  
the 3 shots were still weak, but i was getting closer, so i trimmed 1/4" off.

The next 3 shots were all BARELY weak. I had just built this new skinny string(10 strand BCY-X) and I hadn't installed silencer or anything, but I had stretched it out well.  

Well with the arrows just barely weak, I said I'd go ahead and install my cat whiskers.  they made my arrows goes from slightly weak, to slightly stiff! lol.  

So now I know which arrow I will be ordering.  A dozen .300 spined arrows.