Picking the right spine for my arrow

[nuval.J2711]

Hello all. In June, my family and I are going to South Africa to hunt. I have been given the opportunity to hunt a few of the days with my bow. I shoot a 60lbs bear attitude, the only struggle so far is finding the right spine for my arrows. I have been told that at 60lbs, a 400 spine is better, and by another person that a 500 spine is better. As of today, i am shooting with both and have noticed little differences with speed and that the 400 seems drops earlier. Both of them are Easton Power Flight. Any help would be greatly appreciated

Thanks, NJ

 

[Bhfs300]

To pick the correct arrow you need arrow length, tip weight and pull weight.
The 400's will drop faster because they will be heavier than the 500's.
Go to this web site type in the numbers above and see what Easton says. Your cams are probably hard if it a fast bow.
http://www.eastonhunting.com/
Tom

 

[nuval.J2711]

To pick the correct arrow you need arrow length, tip weight and pull weight.
The 400's will drop faster because they will be heavier than the 500's.
Go to this web site type in the numbers above and see what Easton says. Your cams are probably hard if it a fast bow.
http://www.eastonhunting.com/
Tom

It seems it that the 400s are the best, according to the site. wouldn't the light arrow be better? shooting both with a 125 grain tip

 

[Pheroze]

Hey Nuv,

Interesting discussion. What is it about the lighter arrow that you think would make it better?

 

[nuval.J2711]

Hey Nuv,

Interesting discussion. What is it about the lighter arrow that you think would make it better?

Less weight. it would go faster and farther

 

[Bhfs300]

A heavy tip and light arrow will let the arrow bend and then flex as it leaves the bow. You don't want to light of an arrow since you will lose penetration. How long of a draw/arrow length?

 

[nuval.J2711]

A heavy tip and light arrow will let the arrow bend and then flex as it leaves the bow. You don't want to light of an arrow since you will lose penetration. How long of a draw/arrow length?

draw length is 26inch and the arrows are 28inch

 

[Bhfs300]

The bend and flex is a problem could be throwing the arrow off to the side. You will not be able to get the bow tuned correct. Go with what Easton says is the best stiffness for your set up or you will be guessing all the time when things are not working correct.

 

[BRICKBURN]

Incorrect arrows in a bow will lead to failure. Too much stress......
These examples may not be from spin issues. They could just be from

Follow the charts suggested and always check your arrows before you shoot them.

 

[nuval.J2711]

The bend and flex is a problem could be throwing the arrow off to the side. You will not be able to get the bow tuned correct. Go with what Easton says is the best stiffness for your set up or you will be guessing all the time when things are not working correct.

I will go with the 400s then. thanks for the advice.

 

[firehuntfish]

I shoot a 60lbs bear attitude, the only struggle so far is finding the right spine for my arrows. I have been told that at 60lbs, a 400 spine is better, and by another person that a 500 spine is better. As of today, i am shooting with both and have noticed little differences with speed and that the 400 seems drops earlier. Both of them are Easton Power Flight. Any help would be greatly appreciated

Thanks, NJ

NJ,

I believe I can help you without driving yourself crazy, but I need a bit of feedback....Can you be a bit more specific as to the issues that you are having? Spine charts are a good start, but they are not exact for every set up. The poundage you shoot, arrow length, broadhead weight, and weight distribution along the arrow shaft itself all play a part. As some have mentioned, an improperly spined arrow can create a host of tuning issues affecting the arrow flight and ultimately the point of impact. Before we get into the technical stuff, are the arrows grouping well at 20 yards? At 30 yards? If not, can you visually notice the arrow yawing or fish-tailing in flight? When you say the 400 seems to drop earlier, what do you mean? The point of impact is lower than the 500 at the same distance? ...

 

[nuval.J2711]

NJ,

I believe I can help you without driving yourself crazy, but I need a bit of feedback....Can you be a bit more specific as to the issues that you are having? Spine charts are a good start, but they are not exact for every set up. The poundage you shoot, arrow length, broadhead weight, and weight distribution along the arrow shaft itself all play a part. As some have mentioned, an improperly spined arrow can create a host of tuning issues affecting the arrow flight and ultimately the point of impact. Before we get into the technical stuff, are the arrows grouping well at 20 yards? At 30 yards? If not, can you visually notice the arrow yawing or fish-tailing in flight? When you say the 400 seems to drop earlier, what do you mean? The point of impact is lower than the 500 at the same distance? ...

I am drawing 60lbs and shooting with 28inch arrows with a 125g broadheads and a 26 in draw. I'm not sure what you mean about arrow weight distribution. The impact seems to be lower at the same distance but the groupings a good. No fish tailing that I can see.

 

[firehuntfish]

I'm not sure what you mean about arrow weight distribution.

Many modern carbon arrow shafts are now built with more weight forward in the shaft. Most hunting arrows will perform the best with this configuration. The weight distribution can be tweaked by cutting the arrows and changing the weight of the broadhead....But, lets not get ahead of ourselves just yet... That's a very fine tuning adjustment...

If your groupings are tight, and you do not see any visible fishtailing or porpoising of the arrow in flight, what is the problem that you are trying to address? The lower point of impact of the 400 arrow is likely because it is heavier than the 500 as someone already suggested. But the speed versus weigh issue from a 400 to a 500 spine arrow of the same style and brand should be minimal at best. You go with the spine that flies the best...How low are we talking a@ 20 yards? How tight are your groups? 2-3" groups or less @ 20 yards and I would call it a day and go hunting...

 

[nuval.J2711]

Many modern carbon arrow shafts are now built with more weight forward in the shaft. Most hunting arrows will perform the best with this configuration. The weight distribution can be tweaked by cutting the arrows and changing the weight of the broadhead....But, lets not get ahead of ourselves just yet... That's a very fine tuning adjustment...

If your groupings are tight, and you do not see any visible fishtailing or porpoising of the arrow in flight, what is the problem that you are trying to address? The lower point of impact of the 400 arrow is likely because it is heavier than the 500 as someone already suggested. But the speed versus weigh issue from a 400 to a 500 spine arrow of the same style and brand should be minimal at best. You go with the spine that flies the best...How low are we talking a@ 20 yards? How tight are your groups? 2-3" groups or less @ 20 yards and I would call it a day and go hunting...

2-3" groups, and maybe .5-1" down from the 500 at 20yards

 

[firehuntfish]

Okay.... An inch or 2 lower @ 20 yards between 400-500 spine arrows in nothing to even be concerned about. It's the flight of the arrow that we need to worry about....Now, when you practice again, walk back to 30 yards and shoot another group using the same 20 yard pin. If the bow is roughly in tune you will still group in the center, but obviously the group will be lower. If your group opens or if you group everything low right or low left, you have some tuning issues to address which we can fix... If the group remains good and just lower, I would be happy enough with that.

 

[nuval.J2711]

Okay.... An inch or 2 lower @ 20 yards between 400-500 spine arrows in nothing to even be concerned about. It's the flight of the arrow that we need to worry about....Now, when you practice again, walk back to 30 yards and shoot another group using the same 20 yard pin. If the bow is roughly in tune you will still group in the center, but obviously the group will be lower. If your group opens or if you group everything low right or low left, you have some tuning issues to address which we can fix... If the group remains good and just lower, I would be happy enough with that.

Thanks. I will make sure to get out to the range this week. Thanks for the help.

 

[firehuntfish]

Anytime... Let me know how it goes...

When you go to practice, take some 100 grain heads to try out as well. See if they make your groups better or worse. It's a small weight adjustment that can really tighten up a group if the spine is a little off or you have too much weight forward.

Also, be sure to practice and tune with the broadheads that you intend to hunt with. There are still a few broadhead styles that DO NOT fly like field points. If broadhead tuning is needed, that's a whole new can of worms that I don't even want to get into at this point, and I would have you avoid if at all possible. Go to the range and them we will chat again.

 

[nuval.J2711]

Anytime... Let me know how it goes...

When you go to practice, take some 100 grain heads to try out as well. See if they make your groups better or worse. It's a small weight adjustment that can really tighten up a group if the spine is a little off or you have too much weight forward.

Also, be sure to practice and tune with the broadheads that you intend to hunt with. There are still a few broadhead styles that DO NOT fly like field points. If broadhead tuning is needed, that's a whole new can of worms that I don't even want to get into at this point, and I would have you avoid if at all possible. Go to the range and them we will chat again.

Will do. Thanks a lot

 

[BSO Dave]

fhf,
Do you own or work in a bow shop?

 

[firehuntfish]

fhf,
Do you own or work in a bow shop?

No BSO.... I'm just a garage bow tuner. I started working on my own stuff a few years ago because there were no competent bow shops anywhere near me. I live right near a BassPro Shop and after a couple of really bad experiences with their archery shop, it motivated me to start learning. I am fortunate to have a very good friend who did own a bow shop in Georgia. He started me on the basics, and I have been tinkering around for years from there. It's actually not too difficult to tune your own equipment once you learn the basics. For me, tuning the bows and building arrows is as much a part of the experience as the hunting itself.