How do I figure out what spine I want

[Bullet Hole Bailey]

Ok, so at the shop, when i bought my bow, I just grabbed the most reasonably priced arrows that were about the weight i wanted. At that point in time i had no idea that spine affected arrow flight. I still dont know how to tell what spine is good for me. How do you find out what spine size you want and what does it do for you? What will it effect if you have more or less spine?

I am shooting a Martin Bengal
25" @ 60 lbs
No idea speedwise...........around 250 fps i think.

I am shooting Beman Ventures 400's.
I think they are 8.4 gpi


Any info would help!

Thanks

[Jellio]

I have about the same setup as you with a 26" draw and I'm shooting Gold Tip XT5575's. If you go to the GT website they have a chart for picking the right arrow alot depends on the length of the arrow your shooting as well as yourfield tip or broadhead weight.You canalso determine your FOC on that website with some quick measurments of your arrowso you'll need to now a few spec's off the arrows you currently have. Unless your a 3d shooter or a pro you can't go wrong with Gold Tips XT's or the Carbon Express Maxima's

[Bullet Hole Bailey]

thanks man

[Kanga]

The Bemans will be fine

[BGfisher]

All the arrow manufacturers that I know of have a chart for picking the right spined arrow, or close to it. From experience I can tell you you could be shooting a 500 spine. The arrows you are shooting, although on the stiff side, should work. The main difference between them and the 500 would be that the 500's are lighter in weight. Not sure you want to compromise any weight though.

With carbon arrows you will find that a slightly stiffer arrow will fly better, especially with broadheads if you have some sort of breakdown in form, such as in a hunting situation.

Id say that if your arrows are flying well for hunting then go ahead and use them. If you want to try some 500's then that's what the rest of the year is for.

[Bullet Hole Bailey]

Ok, thanks guys

[archer 2]

The 400's at 25 inches and 60 lbs is definitely stiff. You could shoot them at 70 lbs but if they group for you , go for it. You have plenty of latitude if you want to try a heavier points.

[Straightarrow]

What will it effect if you have more or less spine?

If the arrow doesn't flex properly when shot, it will have a tendency to hit left or right of the target. Your fletching is what helps straighten out the shot. However, a broadhead tends to resist the help fletching adds. Therefore, it's good to get spine correct. This way, your arrow has the maximum forgiveness built into it. This can make a huge difference in wind or if you hit a small twig, leaves or grasses.

The best way to design your arrow is to pick an adequately heavy tip. I can't recommend less than 125 gr for any setup and I firmly believe most (especially beginners) will benefit from much heavier tips. After you determine tip weight, it's fairly easy to get into a spine range from mfgr charts. Pick a slightly stiff arrow. Then you start by building one at an inch or two longer than you expect to shoot and then bareshaft test it. By trimming 1/4" at a time from the shaft, you can make this bareshaft fly perfectly (with a field tip) to your target. At this point, you know you have the spine correct. Hopefully, at the same time you choose the heavier tip which will give you a higher FOC, which adds to stability and penetration of the arrow.

If this process is confusing, research it and study it until you learn it. It's by far the most important aspect of tuning a hunting setup. Keep in mind, judging the quality of your arrow flight with field tips can't be done with fletching attached.

[nodog]

I know what your thinking. Your thinking youwant toavoid wasting anymore money. Get that thought out of your head and become a puppet of the archery industry like the rest of us. Might as well get that place ready for all the stuff you don't need, or work.[:@]