Spine? IBO ABO? etc...?
08-30-2008, 03:46 PM
#1
Giant Nontypical
Thread Starter
Join Date: Jan 2008
Location: IL
Posts: 6,575
Spine? IBO ABO? etc...?
I think I saw it mentioned on here before how to calculate the ideal/best spine etc...for your setup?
I'm not new to archery, but new to all these figures and numbers and what is best etc...
My draw length is 28"
current draw weight 63lbs, would like to become comfortable at 70lbs.
shooting 100gr broadheads.
have a few different arrow setups
don't know exact arrow weights...
1 set is 10gr/in estimated wt... 418grs
2 set is 7.9gr/in.................... 353
3 set is 6.4gr/in................... 307grs
Mainly trying to figure out if I could tweak my setup to shoot even tigher groups by determing an ideal BH weight, and or ideal spine/arrow weight etc...
Is spine just arrow shaft diamter? and what is spine used to determine...?
Thanks.
I'm not new to archery, but new to all these figures and numbers and what is best etc...
My draw length is 28"
current draw weight 63lbs, would like to become comfortable at 70lbs.
shooting 100gr broadheads.
have a few different arrow setups
don't know exact arrow weights...
1 set is 10gr/in estimated wt... 418grs
2 set is 7.9gr/in.................... 353
3 set is 6.4gr/in................... 307grs
Mainly trying to figure out if I could tweak my setup to shoot even tigher groups by determing an ideal BH weight, and or ideal spine/arrow weight etc...
Is spine just arrow shaft diamter? and what is spine used to determine...?
Thanks.
08-30-2008, 06:20 PM
#2
Nontypical Buck
Join Date: Aug 2006
Location: Southern MD
Posts: 2,520
RE: Spine? IBO ABO? etc...?
Spine is theamount of flex or bendof an arrow shaft under certain conditions. When you shoot the arrow it flexes as it leaves the string. If it flexes the correct amount then you have a correctly spined arrow and it will shoot best. If it doesn't flex enough then it is too stiff, too much flexing and it is too weak and either one too stiff or too weak is not ideal. A hunting arrow is usually set up with a slightly stiffer spine than a target arrow.
Someone can look up your info if you list your bow model and its' current setup and your arrow model with its' length and tip weight along with fletches.
Someone can look up your info if you list your bow model and its' current setup and your arrow model with its' length and tip weight along with fletches.
08-31-2008, 12:43 PM
#3
Nontypical Buck
Join Date: Feb 2007
Location: Balt, MD (orig: J-town,PA) The bowels of Hell!!!
Posts: 2,188
RE: Spine? IBO ABO? etc...?
Just to add to bruce's good post.
Shaft diameter has a small part to do with the spine. There are very skinny arrows that have stiff spine and very fat arrows that have weak spines. It all depends on the thickness between the inside and outside diameter, the overall diameter, and shaft material and design. Even arrow weight between manufacturers may vary.
If all 3 arrow you listed are the same exact arrow manufacturer/model the heaviest one will probably be the one with the stiffest spine.
As bruce stated supply your bow manufacturer, the arrow manufacturer/model that you have, the arrow length you intend to use and we can help you out.
Shaft diameter has a small part to do with the spine. There are very skinny arrows that have stiff spine and very fat arrows that have weak spines. It all depends on the thickness between the inside and outside diameter, the overall diameter, and shaft material and design. Even arrow weight between manufacturers may vary.
If all 3 arrow you listed are the same exact arrow manufacturer/model the heaviest one will probably be the one with the stiffest spine.
As bruce stated supply your bow manufacturer, the arrow manufacturer/model that you have, the arrow length you intend to use and we can help you out.
08-31-2008, 02:04 PM
#4
Giant Nontypical
Thread Starter
Join Date: Jan 2008
Location: IL
Posts: 6,575
RE: Spine? IBO ABO? etc...?
Carbon tech arrows, whitetails, rhinos, cheetahs,plan to use whitetails or rhinos for hunting
most likely whitetails Spine for all 3 is listed at .400?
Arrow Shaft lenght: 28"
NAP quickspin ST speed hunters
Matthews drenalin 70#, 28" draw, current weight 63#
100gr broadheads, muzzy 3 blade, not mx3, also have rage 2 blade 100gr
most likely whitetails Spine for all 3 is listed at .400?
Arrow Shaft lenght: 28"
NAP quickspin ST speed hunters
Matthews drenalin 70#, 28" draw, current weight 63#
100gr broadheads, muzzy 3 blade, not mx3, also have rage 2 blade 100gr
08-31-2008, 03:06 PM
#5
Nontypical Buck
Join Date: Aug 2006
Location: Southern MD
Posts: 2,520
RE: Spine? IBO ABO? etc...?
It looks as if you are marginally weak spine with that setup. Not awful but marginally stiff would be better. If you are going to get up to 70#'s you may want to look at the whitetails, rhino's and cheetahs with a .300 spine. You may also want to look at some other arrows in the .360 spine range, easton, carbon express, gold tips, etc.
Edit: Forgot to chnage the DL to 28" but you are still slightly weak.
Edit: Forgot to chnage the DL to 28" but you are still slightly weak.
08-31-2008, 03:06 PM
#6
Nontypical Buck
Join Date: Feb 2007
Location: Balt, MD (orig: J-town,PA) The bowels of Hell!!!
Posts: 2,188
RE: Spine? IBO ABO? etc...?
If you are shooting the Drenalin with 80% let off your spine should be ok with any of those arrows up to 70 lbs. You may want to use a wrap though to stiffen the spine a little. Try to remember when looking at this that the spine is probably a little stiffer than what is shown. The program uses IBO speed and every bow's IBO differs depending on DL and the actual performance of the bow. Your bow's IBO will not be 320 FPS as listed by manufacturer because that IBO is for a 30" draw length unless otherwise specified.
You need the speed of a known arrow shot from your bow to adjust theIBO speed for your bow and a program like Archer's Advantage to figure out the exact spine. OT2 does not compensate for slower IBO's. So, ifthe program showsthe spine on the low side it is probably actually in the middle or slightly high. I've used this method with this program and have no issues with my arrows.
You need the speed of a known arrow shot from your bow to adjust theIBO speed for your bow and a program like Archer's Advantage to figure out the exact spine. OT2 does not compensate for slower IBO's. So, ifthe program showsthe spine on the low side it is probably actually in the middle or slightly high. I've used this method with this program and have no issues with my arrows.
08-31-2008, 03:21 PM
#7
Giant Nontypical
Thread Starter
Join Date: Jan 2008
Location: IL
Posts: 6,575
RE: Spine? IBO ABO? etc...?
65% let off, drenalin
so lower spine # equals a stiffer arrow? higher spine # weaker/less stiff?
I'm typically at 63lbs, but if I shot more I know 70# wouldn't be a problem, so looking to get there. Always planning to shoot 100gr too, dont think I'll ever shoot 125grs, maybe for something large, but doubtful.
Thanks for the info
so lower spine # equals a stiffer arrow? higher spine # weaker/less stiff?
I'm typically at 63lbs, but if I shot more I know 70# wouldn't be a problem, so looking to get there. Always planning to shoot 100gr too, dont think I'll ever shoot 125grs, maybe for something large, but doubtful.
Thanks for the info
08-31-2008, 03:47 PM
#8
Nontypical Buck
Join Date: Feb 2007
Location: Balt, MD (orig: J-town,PA) The bowels of Hell!!!
Posts: 2,188
RE: Spine? IBO ABO? etc...?
ORIGINAL: salukipv1
65% let off, drenalin
so lower spine # equals a stiffer arrow? higher spine # weaker/less stiff?
I'm typically at 63lbs, but if I shot more I know 70# wouldn't be a problem, so looking to get there. Always planning to shoot 100gr too, dont think I'll ever shoot 125grs, maybe for something large, but doubtful.
Thanks for the info
65% let off, drenalin
so lower spine # equals a stiffer arrow? higher spine # weaker/less stiff?
I'm typically at 63lbs, but if I shot more I know 70# wouldn't be a problem, so looking to get there. Always planning to shoot 100gr too, dont think I'll ever shoot 125grs, maybe for something large, but doubtful.
Thanks for the info
08-31-2008, 04:24 PM
#9
Giant Nontypical
Join Date: Feb 2003
Location: HENDERSON KY USA
Posts: 6,634
RE: Spine? IBO ABO? etc...?
ORIGINAL: davepjr71
If you are shooting the Drenalin with 80% let off your spine should be ok with any of those arrows up to 70 lbs. You may want to use a wrap though to stiffen the spine a little. Try to remember when looking at this that the spine is probably a little stiffer than what is shown. The program uses IBO speed and every bow's IBO differs depending on DL and the actual performance of the bow. Your bow's IBO will not be 320 FPS as listed by manufacturer because that IBO is for a 30" draw length unless otherwise specified.
You need the speed of a known arrow shot from your bow to adjust theIBO speed for your bow and a program like Archer's Advantage to figure out the exact spine. OT2 does not compensate for slower IBO's. So, ifthe program showsthe spine on the low side it is probably actually in the middle or slightly high. I've used this method with this program and have no issues with my arrows.
If you are shooting the Drenalin with 80% let off your spine should be ok with any of those arrows up to 70 lbs. You may want to use a wrap though to stiffen the spine a little. Try to remember when looking at this that the spine is probably a little stiffer than what is shown. The program uses IBO speed and every bow's IBO differs depending on DL and the actual performance of the bow. Your bow's IBO will not be 320 FPS as listed by manufacturer because that IBO is for a 30" draw length unless otherwise specified.
You need the speed of a known arrow shot from your bow to adjust theIBO speed for your bow and a program like Archer's Advantage to figure out the exact spine. OT2 does not compensate for slower IBO's. So, ifthe program showsthe spine on the low side it is probably actually in the middle or slightly high. I've used this method with this program and have no issues with my arrows.
Hope this makes sense.