Spine question

[Dutchman]

I know what the 3 Rivers Arrow Selection chart says, but I'm interested in what your experience tells you.

I have a Bear Byron Ferguson Patriot bow, AMO 64", 55# @ 28".  My draw length is 31". I've been fooling with the brace height and it seems to perform well at around 6-1/2" to 6-3/4" or so. If it makes any difference in arrow selection, the bow seems to perform best with a D97 Flemish Twist string.

What spine would you select in cedar arrows for this set-up and why?

[Dutchman]

Anyone?

[**DONOTDELETE**]

I would think 70-75# would work well, but that is for wood. I don't know what it would be for the others..

That's
bow 55@28 drawing 31/+3" +10#
bow +5#
string +5#
Don't know what point weight if under 160 grn +5 ( 70-75# )160 & over +10 ( 75-80# )

[cvarcher]

Id say 80-85lb spined shafts .remember you need to add 5lbs per inch over 28" and Id like to leave one extra inch of arrow over draw length for broadhead clearance .so 4 inches times 5lbs is 20lbs added to a 60-65lb spine that the bow will pull at your draw of 31".

[Orion]

CV archer.  I agree with your recommendation, but your calculation is a little off.  The 5# per inch is added to the 55#.  Thus, one would add 15# for the three inches extra draw arriving at 70#.  Add another 5# for a fast flite string.  That brings you to 75#.  I've also found that most bows perform a little better if they're overspined a little.  That's why I would go to 80-85#.  75-80# may also work for you Dutchman.

[Dutchman]

I appreciate y'all's input. Many thanks.

[cvarcher]

Orion, but he's not drawing at 55lbs he's drawing around 63lbs.So thats what you have to match with 32" length arrows.There is some leeway as well such as the weight of points, tapered shafts, type of bow etc. Sure enough 5lbs under may work just as well.

[SlowBowinMO]

My Patriot is a hard fast shooter but the shelf is cut pretty shallow (not even to center) which has a HUGE effect on spine requirements.  If your draw was 28" I'd tell you to test both 50-55's and 55-60's and you'd probably end up with the 50-55's.  So to compensate for your extra long draw of course you'll need to add to that...I really think that bow will shoot something around 65-70's well, that is based on my experience with the Patriot.

For every archer who is underspined I'll bet you can find 10 who are overspined, we are funny that way.

[Dutchman]

That does it! I'm ordering the test kit!

Thanks much guys.