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Main Boards => PowWow => Topic started by: oneraindog on May 15, 2010, 02:09:00 PM

Title: Spine weight ???
Post by: oneraindog on May 15, 2010, 02:09:00 PM
ok so i have this loose understanding of spine weight being the relationship between the force behind the arrow at release and the amount of flex in the arrow around the bow and through flight. about right?

so, how important is it to have the spine just right?

i recently went to an archery store to buy some new arrows and new limbs for my take down. i had been shooting a 45 pound bow with arrows rated for 55/70 lbs. the new limbs are 55lbs and the guy sold me arrows rated for 65/80.

his claim was that spine weight in a recurve is not very important. i am not qualified to question that but something doesnt seem right about that.

does bow weight need to match spine weight just right?

if i shoot the 65/80 arrows from the 45lb limbs will performance be adversely affected??

thanks for reading all of this. hope it made sense.
Title: Re: Spine weight ???
Post by: Don Stokes on May 15, 2010, 05:53:00 PM
Spine is important, no matter what style bow you're shooting. Critical, in fact. If you don't have the right spine, you can get by with field points if you're reasonably close , but it must be exactly right to shoot broadhead arrows well. His claim is bogus as you suspected, but the arrows may shoot well, because recurve bows need considerably more spine than the draw weight number. Arrow spine was originally based on self bows, and bows with more advanced designs need more spine than self bows at the same draw weight.
Title: Re: Spine weight ???
Post by: oneraindog on May 15, 2010, 07:02:00 PM
so if my draw weight is 55 the 65/80 spine arrows will do ok but the 55/70 spines would be better? or the difference will be negligible?

what about shooting the 65/80s from a 45 draw weight?

the thing is that my groupings are not tight enough to be a reliable gauge of what the differences would be but my worry is that as a beginner if things are off then i will be doing more harm than good as i practice.
Title: Re: Spine weight ???
Post by: Don Stokes on May 15, 2010, 10:44:00 PM
oneraindog, I suggest you try them both and see what happens. There are several things that can make a difference, like the length of your arrows and the weight of the points. If your arrows fly well without any obvious kick or wobble, you aren't likely to do yourself any harm in practicing. As you get better and more confident in what you're doing, you can fine-tune. This is a great site to get the information you need, and if you can make it to a local 3D shoot you can pick up lots of good information by rubbing shoulders with more experienced archers. Most traditional archers are very willing to help someone get things right.
Title: Re: Spine weight ???
Post by: oneraindog on May 15, 2010, 11:11:00 PM
good deal. thanks for the help.
Title: Re: Spine weight ???
Post by: robtattoo on May 16, 2010, 12:25:00 AM
Have a look at THIS (http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=6;t=005121)
Title: Re: Spine weight ???
Post by: oneraindog on May 16, 2010, 01:49:00 PM
thanks for the heads up
Title: Re: Spine weight ???
Post by: Fletcher on May 16, 2010, 08:14:00 PM
Like Don, I consider spine to be critical.  With paper tuning, I will get a 3 lb spine range that will shoot the "bullet hole".  Outside of that 3 lb range, I can see the change in spine and arrow flight.  Fletching will fix a lot, but the closer to right on you start, the better off you will be, esp when you mount broadheads.
Title: Re: Spine weight ???
Post by: Rackman on May 19, 2010, 02:10:00 PM
The spine of the arrow has to match the spine of the bow.  Check out Stu Miller's Dynamic Spine Calculator   http://www.heilakka.com/stumiller/   .  This chart will help you find arrows that will match the spine of your bow. Even if your bow is rated at 55lbs, the dynamic spine differs based on many factors, such as actual draw, center shot or not, type of string.  The arrow spine is the same differs based on length, weight of point, weight of insert, weight of nock, length of fletch.  If you take a look at this chart you will see what I'm talking about.  Hope this helps.
Title: Re: Spine weight ???
Post by: Flying Dutchman on May 19, 2010, 02:47:00 PM
QuoteOriginally posted by robtattoo:
Have a look at THIS (http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=6;t=005121)  
I guess you are wrong here! The link you are giving us is related to the SHOOTERS forum and not to POW-WOW.

As a matter of fact, this link says: "The above topics should be posted on the PowWow"

So the poster has every right to ask this question here.
Title: Re: Spine weight ???
Post by: Flying Dutchman on May 19, 2010, 02:47:00 PM
here went something wrong, can't delete anymore, sorry
Title: Re: Spine weight ???
Post by: Bjorn on May 19, 2010, 03:12:00 PM
Spine and picking a spot are among the few things that really count-having a string is important too.  :bigsmyl:
Title: Re: Spine weight ???
Post by: Rackman on May 19, 2010, 04:08:00 PM
Flying Dutchman, the link that I gave is related to spine, which is what I was talking about. When I clicked on your link, it actually says that spine related questions are better answered in pow wow.  I am relatively new to this site, and am only trying to help out, as most guys are. So I don't understand how am am wrong.