Too much spine possible?
 

I shoot a 70 pound single cam bow and use a TKO dropaway rest along with a string loop. Is there a downside to having too much spine besisdes the arrow may be heavier?

RE: Too much spine possible?
 

THere is a chance they might not group as well.

RE: Too much spine possible?
 

Scott, you have it right on the money. Arrows heavier that recommended on the arrow charts can be tuned to perfection. The positive: increased kinetic energy. The negative: slower arrow speed. Problems begin when shooters start to drop well below the recommended arrow spine. Tuning problems, string and cable failures and the big one, limb cracking or failure are all inherent traits of under spined arrows.

RE: Too much spine possible?
 

seems the bows will accept heavy spine, but they don't like to light of spine. I hunt heavy spine on my hunting arrows and my bow loves it..

RE: Too much spine possible?
 

An arrow with a stiffer spine is not necessarily heavier. Take a 2512 Easton (deflection:.321, weight at 29": 281 grains)and compare it to a 2020 Easton (deflection: .426, weight at 29": 392). There are also heavier carbons out nowwith less spine.

But to answer your question, yes there is a down side to being overspined. What you want is the correct spined (not over or under). What you want is the arrow which shoots through the centershot of a perfectly tuned bow.

RE: Too much spine possible?
 

I have heard that too much spine can be a bad thing. I am curious if you or anyone else knows what happens during the firing of the arrow that throws things off. I am not questioning whether you are right or not, just trying to understand why it does it.

RE: Too much spine possible?
 

If shooting a release (where the significant side to side movement caused by an imperfet finger release is eliminated) what downside is there to being overspined? True, its hard to paper tune accurately, but what practical detriment is there? It seems even with broadheads, there would be litle downside. I have read that even with a release there is still notable up and down flexing and thus perhaps the weaker spined arrow will absorb it and revert to true center sooner, but isn't it harder to get that stiffer arrow oscilating to begin with? Also, is the stiffer arrow going to mean better penetration becaue less energy is expended oscilating? I'm far from an expert in all the nuances of archery. However, noone has provided an explanation that clicks (may be I'm simply to thickheaded to understand). Does the equation change if a drop away rest is used and there is no arrow contact to be worked upon by some up and down oscilation? I've experienced first hand the detriment of weak spined arrows with fixed broadheads--the eratic arrow flight is quite apparent. I've simply not experienced any downside with overspined arrows. Please share your expertise, experience or wild ass speculation!

RE: Too much spine possible?
 

Honestly I feel that the overspine is not an argument that has any definite answer. You will have to see what works on your setup.

I personally shoot a GoldTip Pro 22 series (spine of .300) cut at 28" with a 85 grain tip, which is way overspined according to everyones charts. I have no problems with tears, and it bareshaft tunes well. I have a friend with a 65lb Mathews Outback, he is shooting 27" X-Cutters (.250 spine) with 65 grain points and his bow shoots bullet holes and bare shaft tunes excellent as well. We both shoot these arrows and setups because they are wide diameter arrows and catch a few extra lines for us in competitive 3D, and because they are both very close to the 5 grain per lb IBO minimums.

On the other hand, I hear of people claiming to have bad tears due to overspined arrows all the time on different forums. I really think it is all in how well the bow is tuned, and who knows what else. I have never specifically seen issues myself though with my equipment with overspine.

RE: Too much spine possible?
 

I'm not sure what you are saying. What I am reading is that side to side movement is elliminated when using a release. In that case what would be the difference in using an underspined arrow with a release?

Papertuning will show how the arrow is coming off the bow (I used to use a max of six feet on the compound, I don't papertune my longbow). If the arrow is underspined, or overspined, the hole should note the difference assuming the person shooting the bow has perfect or close to perfect form. It is easy to understand that an arrow coming off the bow straight will not need as much stabilization from the fletches as one that is coming off the bow overspined or underspined. Either way, if the arrow is not coming off the bow straight to begin with, accuracy will be effected. Minor inconsistancy in arrows, fletching, broadheads, form, etc, willmagnify the effects.Paper tuning, if done right, should get you very close to a good tune. However, if you are getting bullet holes with papertuning and you are not close to centershot, then something is wrong.An over spined arrowcan tuned to a bow, however, if the tune is not at or close to centershot, an new arrow size is needed.

RE: Too much spine possible?
 

Good explanation.....

I feel overspine tuning problems are mostly magnified by a improperly tuned bow, or magnified by bad form.

RE: Too much spine possible?
 

I have 2117's that are cut to 26 1/4 inches, with a 100 grain tip. With that arrow I can shoot up to 72 or 73lbs. I would call that overspined. On my old 10 year old bow, I could get perfect bullets at 3 feet and I could group pretty dang good I think. I still have yet to try to tune my new one, basically Im too lazy.

RE: Too much spine possible?
 

Just wondering why you consider your arrow overspined. Easton charts (which I don't trust 100%, I have found their charts to be on the stiff side) calls for deflection between .340 and .390 in their aluminum lineup. Your 2117's have a .400 deflection.

RE: Too much spine possible?
 

It's difficult to find an arrow too stiff for a modern compound shooting a true centershot with a release. I always shoot overspined carbon arrows with all my compound bows. I have no problem getting great broadhead flight with such arrows. On the other hand, borderline spined arrows have caused me many headaches. The spine variation in the typical dozen carbon arrows is so large, that you end up shoot some weak and some stiff, which gives terrible groups. Tune your bow for a stiff arrow, and groups are much smaller.

With aluminums it's much easier to get the correct spine withoug going too weak or two strong. Also, if you're not shooting a modern compound, then too stiff is not good.

RE: Too much spine possible?
 

I'd have to disagree with you. Unless my 2004 Darton Tundra Extreme (311 fps)would be considered outdated. Anyway, I started out using a 2317 (deflection .297) which was the same arrow that I used on my 2002 Parker Feather Mag, both set at the same poundage. Anyway that arrow gave me a very stiff reaction. I was already using a 145 grain tip, and the arrow was cut past my knuckles. I could get the darton with the 2317's tuned pretty decent with field pounts but fixed broadheads were tough, and I wasn't all that happy with my rest set at 1/4" off center. I expermented with a few other combinations, and ended up using a 2216 with a .375 deflection. The rest was sitting at center point now, and my fixed broadheads were flying very true. In fact in elk camp last year, I was able to shoot a 2" group at 50 yards (three arrows) at an elk target. Luckily, I had witnesses for that one.

But, here is what I think. Not all bows are going to call for the same arrow deflectioneven if they are set at the same poundages. There are just too many variations of cams out there. And there are so many differences in nock travel (which has a large effect)between various bows. Arrow manufacturers put out charts which are nice of them, but they are really only a starting point for any particular bow. It would be so nice if the bow manufacturers started testing (which shouldn't be very hard) and giving out recomendations of proper arrow deflectionsfor their particular bows. That would help solve a seemingly problem.

RE: Too much spine possible?
 

As I mentioned, if your shooting aluminums, then ideal spine is best.

RE: Too much spine possible?
 

Just reread prior posts, and I guess I can not see where that was mentioned.

Anyway, I agree that when carbons are offered with spine deflection in increments of .1, it can be hard to get exactly the right spine, and in that case, I would agree that it would probably be better to error to thestiffer side if you absolutely have to. However, there are always some things that can help to get it right. For instance; adjusting poundage of the bow to fit the arrow (I would suggest starting at midrange so there is adjustments either way, increase poundage to get weaker reaction, decrease poundage for stiffer reaction), cutting the arrow to the correct lengths (the longer the arrow, the weaker the reaction, shorter the arrow, the stiffer the reaction),and using the correct point weight (lighter the tip, stiffer reaction, heavier tip weaker reaction). Using compinations of the above mentioned techniques can sure get you very close, even with a carbon.;)

RE: Too much spine possible?
 

Like I said, coming close with a carbon, usually doesn't work. Most carbons have such huge spine variation in a dozen, that attempting to get close, usually leaves you shooting some weak and some stiff. This is very bad in my experience. On the other hand, I've shot very stiff carbons, with broadheads, and had no trouble grouping.

RE: Too much spine possible?
 

Like I said [8D][8D][8D], it is better to be on the stiff side with carbons if it is absolutely necessary. Like I said [8D][8D][8D], with deflection differences in .1 increments usually offered in carbon, there are techniques that can getan individual veryclose. And maybe even shot better then good groups. ;)

straightarrow, I think we are saying close enough to the same thing. nuff said for me anyway.:)

RE: Too much spine possible?
 

Actually, I think we saying something quite different, or I wouldn't keep responding.;)

I'm attempting to say, don't shoot your all-carbon arrows with the exact correct spine. I think they should be shot on the stiff side. The average hunter shooting all-carbon arrows will find spine variations averaging around .020 - .050 in a typical dozen. How can one possibly shoot such a dozen with the exact correct spine? Attempting to do so, will result in some pretty poor broadhead groups (in comparison with how good the groups could be). The ideal way to shoot such arrows, is to spine test them, align cock fletch to the stiff side and then shoot them so they all fly stiff.

I wouldn't keep posting this, if I didn't think it was important for the average hunter shooting an all-carbon arrow, to understand this. As to the orginal question about whether you can shoot them too stiff, I've never found one too stiff to tune to a good group. If you're hunting very large game with a 900-1200 grain arrow, you'll find it very difficult to shoot an exact correct spined arrow. Yet, hunters are taking such game with super heavy arrows all the time. In many instances, the advantages of heavier, stiffer arrows, outweigh the advantages of a more correctly spined arrow.

Anyway, I've too have said enough and will leave it at that...

RE: Too much spine possible?
 

You're exactly right, we we not speaking about the same thing. I was speaking more in the lines of having matched arrows. Variable deflection readings within a batch of arrows can most definetley create problems. You are correct that lining up the spine (in the true sense of the word) can most definetely help. And that would even go for matched arrow, even aluminum (I do it anyway). See attached:

http://forum.hunting.net/asppg/tm.asp?m=1129052&mpage=1&key=bearing&# 1129950

Thanks for your explaination.

RE: Too much spine possible?
 

Not sure what this means to anyone else but me. I have the same 2004 Darton Tundra as Bobco. I shoot @ 29.5" draw, 61# and a loop. Last year, I was shooting 3-60 ACCs (28.5") which are most likely overspined. They shot great with broadheads. This year, I inherited some even stiffer arrows, Carbon Tech Cheetah 55-80s which are supposed to be just coming into their spine range @ 75# with my draw and arrow length. I somehow am shooting as well with this combo as any arrow I have used. Broadheads have been hitting right on with field points, and grouping as well as I can shoot. I was actually thinking about selling these arrows, and getting ones that were spined for the bow, but the way they have shot for me, I just can't see the point. I guess the only thing to take from this is that you don't really know how arrows, or bows for that matter, are going to work for you until you try them.:)