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chad
01-21-2012, 08:09 AM
I have always shot 30 inch 5575 arrows out of a 65 lb bow and have been able to tune it well. I have been looking at buying some new arrows and noticed that I'm at the upper limit if not over goldtips recommendation for spine. turns out that they recommend a 7595 shaft for a 30 inch arrow. Is this something that goldtip did recently or have I been shooting the wrong arrow for 10 years? I usually have my bow turned down to around 62 lbs so I guess its not an issue but I have been wanting to crank it up to peak(70lbs) and I'm worried I wont get it to tune. anyone have a thought on this?

ontarget7
01-21-2012, 09:16 AM
We would need your draw length ? What bow you are shooting ? IMO arrow charts are at best a very rough estimate. They do not calculate every bows individual specs. The biggest factor is speed/fps and this has changed a lot over the years. Another note spine is measured at 28" raw shaft and there are many variables that can change spine. For instance length of shaft, tip weight, arrow wraps etc and fps all change ones dynamic spine which is basically what counts. You have static spine and that is what a carbon arrow is tested at raw shaft and that does not change and will remain content throughout the life of the arrow. The other factors that I mentioned will in fact change that same arrows dynamic spine

chad
01-21-2012, 09:25 AM
my bow is a bowtech pro 40. I shoot blazer vanes with a wrap. 100 gr tips. 29 inch draw. arrows wiegh in at 403 grains total and are flying at 273 fps

ontarget7
01-21-2012, 09:36 AM
my bow is a bowtech pro 40. I shoot blazer vanes with a wrap. 100 gr tips. 29 inch draw. arrows wiegh in at 403 grains total and are flying at 273 fps
With your specs and moving up to 70# I would consider going to the 7595's cut at 28" raw shaft. This would put you in the range for overall best performance.

ontarget7
01-21-2012, 09:41 AM
Another note. Anytime you change an arrows dynamic spine you will want to re tune. To many people switch arrows or change tip weight etc without re tuning. More than likely you will have to change your center shot when doing these things to get the most out of your set up.