Cool, thanks.

So, do you go with the stiffer spine when it falls somewhere in between, in this case a 400? Suggested Spine: 0.450 (0.455)
And what is the number in the parentheses?

 

The .450 is the recommended shaft, the # in parentheses (.455) is the calculated number. Keep in mind that this is a victory program so they are going to steer you to the next stiffest spine that they make, other companies make .330, .340, .350 etc.
If shooting a fixed broad head I would go stiffer if the numbers are close.

 

Thanks for this. I'd seen some tables but they didn't go above 150 grains for the broadhead.

 

This will be very helpful.

 

the IOS app for spine software is $1.99 and worth every penny.

 

thanks for the heads up!

 

use the victory one all the time.

 

Yep. Victory Archery Spine app powered by Pinwheel Software. ;-)

(actually draw length is not critical, shaft length is)

The draw length is assumed from the shaft length...so it is still important and used in the calculation.

 

One caveat not all carbon arrow are made the same so while this may work for victory arrows it may not for gold tips etc. For one thing its recurve IBO fps speed seem very high to me for most recurves that are closer to 180- 210 fps than the speeds listed in the spine calculator.

 

Not sure what you mean, you enter YOUR bow's IBO speed. All the calculators are a starting point. Regardless of the arrows manufacture, .350 spine means that the static arrow deflects .350" under load. I have seen a lot of manufacturers that don't meet the specs printed on the arrow, so yes there are variances, the weave shafts I have tested probably differ the most, but using this software is still better than guessing, and for people who are off the charts with high FOC front weight I think it really helps. Bottom line, if you want perfection, you have to shoot it in and tune shaft length and point weight, I doubt most people do that. I think this is a very useful tool for all the people posting the Hows my spine questions, and they can easily see what adding/ subtracting point weight and shaft length do to the dynamic spine.

 

Ive used it, good little tool.

 

Thanks

Sent from my SM-G965U using Tapatalk

 

This is a very useful piece of information! Thanks for sharing!

 

I haven’t read all these posts but if you enter IBO speed and that’s not what your bow is shooting, you could end up weak or stiff also. This is about the only reason I ever chrono my bows, so I know what they are actualy shooting. Usually comes out same shaft recommended, but not always.

 

@ PSI@Work

Hi! Can you please explain why the Victory arrow guide gives me results other than the qSpine app? Specifications: Hoyt factor 34 = 29.5 DL; 59lbs, IBO 330; let off 75%.
VAP.166 350 spine, 28.5 cut shaft C2C; 140 grain point; bohning air vane; wrap 5 grain; pin+tophat protector ring 17grain; pin nock beiter hunter ~5 grain.
The Victory arrow guide shows a result of 400 spin, and qSpine 350 (dynamic 356).

I also have a vap sport 400 spine, 28.5 cut shaft, with 110 grains, the other specifications are the same as the 350 spine arrow. The qSpine app shows that the arrow is to soft for the bow. I need to buy more arrows, but I don't know which one to buy. The groups I get are pretty similar at 50 meters. Paper tuning and bare shaft tuning I didn't do.
The difference in values ​​of Victory arrow guide and qSpine app confuses me, as arrow guide is powered by Pinwheel Software, as is qSpine.

I shoot FITA / Field / 3D and need a more or less "universal" arrow or at least a guidance on which arrow to choose for which discipline.
Thank you in advance.

 

>>Can you please explain why the Victory arrow guide gives me results other than the qSpine app?

Simple reason is that the Victory web app does not include all the same inputs as the handheld or desktop. The web app assumes certain things based on the inputs you do make.

With the web app, if the spine calculated falls between a shaft model offered, the app pushes you to the closest match available.

The desktop version available for Mac and Windows OSes is still a "free trial".

I shoot FITA / Field / 3D and need a more or less "universal" arrow

The best arrow for FITA or Field may be one that is slightly weak...for better long range groups. If your 3D arrow needs to be a "line cutter", then you probably wouldn't use the same shaft for FITA.

 

A victory for me was switching to Gold Tip Pierce Platinums:wink:

 

thanx for clarification