That is a loaded question. I say that because some bows actual prefer a stiffer shaft that the calculators would tell us is too stiff. Normally, you want the correct spine because it is important that the arrow have the proper flex. I would suggest experimenting with different arrows to see what your bow likes.

 

Thanks gcs, I already know what my bow likes. I'm just interested in down range consistency from shooting an arrow that's too stiff.

 

i was using 26 inch 340s from a 65 pound bow, way over spined, its very sensitive to bowhand torque, they grouped great but never could get good arrow flight. the slightest change in grip pressure would turn an extreme nock left into a huge nock right. use a spine rated correctly for your bow

 

tpcollins
I didn't have as much of a drop as you, went from 68 to 63 and kept the same arrows. I would think a lot depends on where you are in the range to start with. If you want to know effect down range, I always use a fixed blade broadhead (thunderheads) as my test. If they fly with my FP's, as a hunter, I think I am good to go. If you think they are too stiff, just add a little tip weight so they will flex a little more. I use Gold Tip combo's for the added weight, you could use set-screws. I am not a pro by any means on arrow selection, but from my experience you can get away with a little too much spine a lot more vs. not enough.

Ches.

 

My bad - I'm sorry if my post was misunderstood. I am not trying to find an arrow for my bow, or experiment with various spines to find what suits my bow.

I'm trying to understand the end result from the arrow's flight characteristics when a bow shoots arrows that are too stiff. Will they fishtail all the way to a 40 yard target but maintain a 3" group or will it be more of a 24" group scattered all over the target?

 

I just stumbled across this 8 year old post from Deezlin, makes sense to me . . .

Actually by Easton's Tuning Guide it is about groupings at different distances for release shooter mainly. If you have an absolutely perfect release and very consistant arrow spine properties, as has already been stated the arrow will probably just be slower.

Too stiff of an arrow tends to have a very tight grouping at close range and a wider group as range increases. The release become more critical because the arrow will stabilize before it has corrected to the flight path.

Too weak of an arrow tends to have a very large grouping at close range and a narrower group as range increases. The release become less critical because the arrow will stabilize eventually to the flight path. These arrows have very little spine variation. Most long distance target shooter like to push a weaker arrow for trajectory and will tune the bow and the arrow together.

Properly spined arrow give a balance to both and acheive good groupings over a much broader distance. However, the hunter using broadheads has and additional steering device in front and needs to shoot a stiffer arrow to minimize these steering effects while still retaining as much forgiviness as possible.

Stiff arrows can be tuned by cutting long and adjusted by either decreasing length or poundage or increasing point weight.

 

I can attest to this. I shoot 250 spine with 150g tips out of my 29" #70 testament. Stupid teenage mistake that now I'm stuck with for awhile. However indoor they shoot great. But if I get out to the field I have to make a perfect form shot otherwise they're all over. You can see this in some groupings (if you'd even call it a group) I took pictures of.

You can see from the xs that those were perfect shots. However any mistake I made was shown dramatically.

 

I have shot from 400 spine all the way to 150 spine arrows from my 60 lb specialist and I can't tell a difference, they all tuned just fine with good arrow flight and shot very accurate.

 

Same here

 

The only side effect of a stiff arrow is winning.

Seriously with a stiff arrow you tune the bow to it and you. If you can do this, I can't find a negative in being stiff....and can't find a positive in being soft. If you can't get nock travel out of the bow, you aren't going to like stiff arrows.

 

I would throw in a slight caveat......unless you are shooting fingers or trad gear off the shelf, and then too much stiffness could cause some issues.....could, but not guaranteed.

 

Deezlin and tmorelli are correct.
the detriments to stiff spine show up at longer distances, while the detriments of soft spine are immediately evident out of the bow. as bows have become more "truly centershot" and rig tension has become higher, the need for softer spine, or "correct spine" has become much less of an issue dynamically, and much more of an issue, in the "state of tune", of the individual bow.

 

Its all about the nock travel. Good nock travel will allow a stiffer spine.

 

I'm not sure what "good nock travel" is. As stated before, I used the Deezlin tutorial for adding nock sets inside my D-loop and I have zero nock travel compared to the slo-mo videos I've seen. Is that considered good?

 

You may be able to tune your bow to it, but the basic answer that's already been given is: it depends.

Also, different tuning methods (walk back, bare shaft, French, paper, etc.) may produce drastically different results... one test may show it tuned well, the other may not. At least I've always had this problem when shooting arrows too stiff... paper tuning generally goes in the toilet first IMO.

When it comes to the end of the day - can you fletch your arrows appropriately to make up for the stiffness in spine so the arrows hit the X at multiple yards? If so, drive on.

 

Bet your bow would tune fine with over spine.
DB

 

I always just tried to get a good between the heavy and soft arrows. I have the invasion and the shops around me recommend 350's

 

I agree, it depends on a bunch of things: Consistent form and grip, state of tune of bow (will it kick rt or lft, up or down?), consistent arrow spine (I nock tune all my arrows to leave the bow the same)... Once all those items are figured out for sure all you need are some different weight points and group tune from 50-60 yards.

 

I shoot very heavy arrows and over spine my setup all the time....they fly great with broad heads. IMHO if you are shooting a shoot through rest and release too much spine becomes less important and like said earlier in the thread with broad heads over spinning the arrow a bit even helps. I have shot 2219's off bows that were setup with 27 inch arrows at 65 pounds and that pretty over spined but they still shot well with broad heads.

 

Eman, you need to get the exaggerated thing out of your head. The whole concept is a human confidence thing that you are using to justify your shooting, you even comment that your shooting wasn't that good and blame the poor grouping on the arrow. Once you get over this thought process you will find that they will shoot equally as good. The things that really make a difference is fat arrows getting blown in the wind compared to skinny arrows.

 

I understand. I had never shot more than 50 yards before those. However I read an article by john dudley yesterday about arrow spine that can be found here.
http://www.dudleyarchery.info/article?download=65:horizontal-impact&start=20

 

This is all just my opinion and observations over 30 years. I do believe you can be under spined but not really overspined. If I had to err I would go to the over spined side. You can always correct this by adding weight to the front end. Also in doing this you change the FOC, which I believe has more of an effect than the actual spine of the shaft. Anything between 10-15% FOC should give you optimum arrow flight. I shoot through paper to see how the flight is and I then leave it alone. I feel all of these different types of tuning is overkill. But each person has to do it their way.

 

actually, they both contribute about equally......
adding weight obviously softens the dynamic spine of the shaft, but it also, as you say, moves the FOC forward, and what that dose is create a longer column between resistance and source of thrust, which also softens dynamic spine.
either way, if your your soft on spine, there's nothing you can do but turn the bow down. if your stiff, as you say, you can always do things to soften the shaft, but more importantly, todays bows, don't necessarily need as specifically matched a spine, because they are all truly center shot, so there's no need for the shaft to flex around the riser to stay on it's intended path of flight.

 

I'm just trying this year some 2315's9(340 gamegetters) on a 61# bow, so far they are tuning real well.

 

The time you will see a difference is switching from FP's to BH's years ago I had nothing but issues because I was underspined and my arrows would never fly right fishtailing / porpoising after several different arrows I thought it was just the bow and the shops would tell me this or that size arrow and never got the right ones. I got a new bow back then and found the place I got it from the Tech there set me up with the right arrow and my arrows fly the way they are too. I switched to carbons thinking the shop again would know and I told them my set up and said better to be a little over spined and they sold me 4560 Carbon Express and they grouped 6 inches different and lower from a fp to a bh which suggested I was underspined. So I returned back to my 2514 and never looked back And my arrows with FP & BH have since grouped the same for me... I think this where some have issues they shoot with FP's and then switch to BH never shooting and think they are ready for hunting and then they are well off the mark being they are not up on spine etc and proper set up... When you realize it is important and get the right arrow everything comes in to place and your shooting improves...

LFM