Aluminum arrow spine

[fedora]

I'm shooting a 47# longbow I'm trying  5575 gold tips with 200 gr tips with good flight, but found that easton 2216s with150 gr tip fly great.  How could this be if 2216 spine is so stiff?

George
U.S. Army Retired
Ranger
Airborne
Air Assault

[Killdeer]

Individual style makes a hige difference in the spine of the arrows you use. Other critical factors are draw length and length of the arrow. Without these, we would be just talking through our hats.

Killdeer

[fedora]

Draw length 28" arrow length 29" 3 five inch feathers.

[DesertDude]

If I remember right 2216 was around a .400 spine  same as GT 55/75

[DesertDude]

looks like a 2216 is a .375 spine

[fedora]

That makes them stiffer, right?

[ronp]

How does the diameter of the two arrows compare.  It could affect center shot if the 2216s are bigger, maybe?

[jkm97]

That's consistent with my experience so far. My Widow likes stiffer aluminums than carbons too...I think it's a diameter thing.

[JimB]

I'm assuming you are only shooting fletched arrows with field points.You didn't mention any bare shaft or other tuning.Fletching will hide a multitude of tuning discrepancies.A fletched,field point arrow might appear to the eye to be flying well but if it isn't truly tuned,the broadhead version won't impact to the same place as the field points.Flight could also be very erratic and that also squanders a lot of your bow's energy which can drastically affect penetration.

2216's are supposed to be spined for 71#-80# bows.I suspect if you strip the feathers off one,you will see problems with flight.

[mahantango]

Agree with JimB.

[fedora]

Thanks, will do.  I bought them to use as footings for my 5575 arrows out if my recurve.  I recently got the longbow and I am trying to match an arrow to it.  I've got some 3555 I am gong to try also.  The spine chart on 3 rivers says 2117 to 2213 with a 190 gr head.  Since I'm shooting grizzly 160s with inserts to bring to 200 I figure the stiffer at 2213.  I just don't want to spend a bunch of money finding the right setup, no matter how fun it is.  I bare shafted my recurve setup and experimented with fletchings until I got the perfect everything hitting the same.  Broad heads and field points.  Unfortunately that cost me a fortune.

[damascusdave]

You need to find an Easton spec sheet to shorten your search...it was easy to find that info until they changed to their new and improved website...those of us who have shot aluminum for a long time often forget to ask this simple question...do you understand what an aluminum  arrow number designation means?

DDave

[damascusdave]

A 2213 is .460 spine and a 2117 is .400 spine so the 2117 is considerably stiffer...2213 is about 10 GPI...2117 is 12 GPI

DDave

[Wudstix]

I have 2216 at 84#, 2215 at 79# adn 2020 at 74#.
 

[fedora]

All I know is the 22 is diameter and the 13 is deflection somehow. Enlighten me yoga. I want to shoot aluminum because of cost, straightness ect. I've been shooting since I was 10.  All wood and carbon up until now.  The hard part is when you get into the higher point weights. All the charts are based on 125 up front.  Is the 3 rivers chart close?

[damascusdave]

The first two digits are diameter in sixty fourths of an inch and the last two are the thickness of the aluminum in thousandths of an inch...two ways an arrow gets stiffer, greater diameter and thicker walls...the 3 Rivers (Stu Miller) Dynamic spine calculator is the best starting point out there...all you have to do is get all of the input information correct and pay attention to the form factor adjustment included as the final step...meaning in the end you still have to tune the set up by shooting

DDave

[fedora]

3555 gt bare shaft great at 29" 200 grain tip.  What aluminum shaft would be similar?

[JimB]

2016 should be real close

[fedora]

Thanks Jim! I'll give them a try.

[SCATTERSHOT]

22 is indeed diameter, but the 13 is the thickness of the shaft wall.


Sorry, this has been answered. Didn't see the second page.