Help selecting weight of heads to tune stiff shafts

[Kanin-maskwa]

Okay so after shooting a while with my Easton camo hunter ( 2018 XX75 @ 29-1/8" arrows and 125 grain field points that are feather fletched with offset. ) I have as expected found them too stiff. ( I'm shooting a 45# recurve T.D. At 28" 60AMO)
Btw they were selected for me by the archery shop I bought them from.
So since I bought 12 I wonder if I should raise the weight of the heads vs buying 12 née arrows?
How much weight would I have to add to the heads to soften the spine equivalent to going down to 2017 or 2016 arrows?
I raised my brace to 7.5" which helped a bit but my bow shoots sweet at 6 3/4"-6 7/8".

I would feel bad about bringing the arrows back since I already retuned my first set and had him refletch them with feather and add another " to the draw length.
Okay advise?
Cheers
Shawnee

[Jeffro]

Buy a range of different weight heads and shoot them.Then decide which ones work best.
This will probably be the last time you let the archery shop choose your arrows for you .


A couple of questions
Why dont you buy a fletching jig and the other bits and pieces and make your own?
If you knew they were"as expected"gonna be too stiff why did you get them?


If your not into wooden arrows you could try some 35\55 spine carbons and they will work

By the way how do you know they are too stiff?I am presuming the tail of the arrow flies out to the right when you shoot them if your bow is right handed?

Good luck with the different weights I hope you find something to work for your alloys

[Nephew]

You can get test kits - http://www.3riversarchery.com/Broadhead ... oduct.html , but instead of going OS for it, you would be better off if you have a chat to John McDonald ("jcm" on here) at Amso 128 he may be able to help you. Mark at http://www.tradbits.com.au/ might have something, too.

[Bent Stick]

Mate at 45# probably should have gone 2016's with 125 grain Field Points, I used to use 2117's with 175 grain Field points out of a 60lb recurve:
2118 is a very stiff shaft probably about a 250 to 300 spine if you can get 200 grains up front and leave the shaft as long as possible you may soften it a little but at 45lb mate i think you might do better swapping them with someone with a much heavier stick chucker.

Good luck with it mate and suggest trying some different shafts and points as suggested above, or just go timber

[stickshooter]

Shawnee I would go back to the shop and demand the right spine to suit the bow,there the ones who are sposed to be the experts.
And to many of them (compound shops)will sell "what ever" to new people who want trade gear because they don't want to know.
cheers
Nigel

[Kanin-maskwa]

Well I think i will give the shop a call and see if I can get new arrows.
I'm not real happy with the fletching job either. I would like to fletch myself but at the moment I'm too time poor.

What would you guys suggest in aluminium? ( I do want feather fletched ) but 4" or 3" ?Helical or offset? I'm leaning to say.....4" helical RH feather fletched Easton aluminium arrows.
2016 with a heavier head or 1916 with lighter heads and what weight heads would it take to get me in the ballpark?

Grrrrr I'm right back to square one...... Well at least I know this combo does not work.

[stickshooter]

go to eastern archery website and go to hunting arrow selection chart
I shoot carbon arrows with 4" helcoil fletching,I also weigh mine up with 6mm pine dowel to give them some weight,580gn per shaft.
or you can put in brass inserts for weight.but if your shooting a 45lb recurve a carbon with a 145gn head will give you about 400gn which would be about right for you.
But you must know your draw length
Tradbits sell eastern powerflights for $60 per dozen shafts check his website www.tradbits.com.au he also do's ali's
cheers
nigel

[Nephew]

Some places will sell you a test kit of three shafts of similar spine to find which is best for your set up, maybe try that? I'm surprised the shop you orignally got your shafts from didn't ask you to bring in the bow for some bare shaft tuning.

[longbow steve]

Well I think i will give the shop a call and see if I can get new arrows.
I'm not real happy with the fletching job either. I would like to fletch myself but at the moment I'm too time poor.

What would you guys suggest in aluminium? ( I do want feather fletched ) but 4" or 3" ?Helical or offset? I'm leaning to say.....4" helical RH feather fletched Easton aluminium arrows.
2117 with a heavier head or 2016 with lighter heads and what weight heads would it take to get me in the ballpark?

Grrrrr I'm right back to square one...... Well at least I know this combo does not work.

Mate, the arrows you are talking about there are just as stiff as the 2018's if not stiffer. Numerous people have told you 2016's will be the correct shaft for your set up. Put the 2018's up for sale in the trade blanket and go from there.
Get Easton camo hunters or the cheaper Gamegetters. Go for 4" plus of fletch for the look and benefit of stabilisation.
Steve

[Kanin-maskwa]

Hi Steve
I checked the site right after I got my arrows and they were not grouping well.
When I put my specs in it shows 2117-2020 as being suitable for excellent durability and penetration.
Now since I told the shop I wanted them for hunting he probably worked off the chart.
Btw I did bring my bow in but he did not really do any such tuning other then we fired one arrow each ( a bit disappointing since I phoned before hand and requested to bring my bow in and get it all tuned and sorted )
He told me he's been hunting recurve for 20 years. There's plenty of hunting pictures up in the shop too. I just thought he would steer me right.
At the moment I'll probably stick with aluminum arrows.
Should I stick with the 120 weight to start? If I get a selection of field points what increments should I get?
So I'm looking at 2016 arrows 4" RH helical feather fletch and 29" shaft ( my draw is 28") but will be shooting broadheads with these too.

Now just need to select point/head weight.

[kimall]

Mate if you can get some shafts and want to send them to me I will fletch them up for you.It may be easier to get shafts instead of finished arrows.
Cheers KIM

[longbow steve]

Righto.

[Kanin-maskwa]

Hi Kim
That's a very nice offer. I'll definitely keep that in mind as I figure things out.
Cheers
Shawnee

[slvrslngr]

Mate, the charts are rarely accurate for trad shooters. They are developed for compound bows and just "adjusted" for recurves or longbows and almost always recommend too stiff a shaft, particularly for lighter weight bows. Listen to what the guys here are telling you. I'd also give TradBits a ring and discuss your needs with them if you want new arrows. As far as point test kits are concerned, they typically come in 25gr. increments if purchased. Send me a pm with your mailing address and I'll send you a few points to play with, I've got 145, 200, 225, and 260gr. points. Be patient with your tuning, you'll get there!

Chris

[Kanin-maskwa]

Thanks everyone.
I've let the archery shop know what's happening and am waiting for their response.
Btw when I wrote 2216 above it was a typo I meant 2016. I edited it but it did not change it in the subsequent quote. So it's not that I'm not listening

I've since had a chance to bareshaft and it just confirmed what I already knew.

Thanks slvrslngr that sounds great. I know it will all be worth it in the end.
I've received the masters of the barebow and it was good to see the tuning in action vs just reading about it.

[Tonylange]

Morning Shawnee, Mate if your interested i can probly send you a test set of Woods if you want a go with timber. Ohh and i'll also second Kimall's offer of fletching.
Hope all goes well mate.

[Kanin-maskwa]

Can I just say the support here has been overwhelming. It's fantastic to be amongst those so passionate about thier sport that they want others to attain the same appreciation and success.
Cheers to you all
Shawnee

[UPTHETOP]

Shawnee have you tried 145 and 160grn field pionts on the shafts you have already might brake the spine down just enough to pull them back into line.

All the best ahhh the fun of tunning.

Cheers Wayno

[Kanin-maskwa]

Well after doing some more research I'm keen to try a much heavier broadhead. In fact I would like to try to get as much FOC I can and end up with a total arrow weight of over 500gr. Maybe these would be good flyers if I get the point weight high enough but I'm still not sure how much weight increase on 29 " shaft equates to dropping the spine by a step.

[GrahameA]

Morning All.

?.. but I'm still not sure how much weight increase on 29 " shaft equates to dropping the spine by a step.

Spine is a measure of shaft deflection and changing the point mass will not change the spine. Changing the point mass varies the dynamics of the shaft. eg It changes the natural frequency of oscillation of the shaft and the Euler loading on the shaft on launch. In addition there are a few other things happening. I am not aware of a freely available set of information that correlates variation of point mass to change in "Dynamic Spine" to change in Spine.

A good project in Mathematical Modelling for someone.

[UPTHETOP]

Grahame ?

[GrahameA]

Hi Wayne.

Grahame ?

Nah. So many lures....so little time.

Plus Jim has almost finished his PhD and will publish a very interesting book a year or so after he finishes it.
http://www.ozbow.net/phpBB3/viewtopic.p ... 18#p114618

Then again I could go and do some more of this stuff. http://www.youtube.com/watch?v=JfAt7E7m ... re=related

p.s. Just to give an idea of how much fun the arrow modelling could be http://www.bio.vu.nl/thb/users/kooi/kooi91b.pdf

[Kanin-maskwa]

Hey Chris
I received the points you sent today. They look great.
Thanks so much these will be a big help!
I'm going to try paper tuning this Sunday, after that I'll cross reference my findings with bareshaft plane testing.
Last Sunday I had a crap day shooting. I stripped my rest off and thought I would give shooting of the shelf a go spent the whole night trying to dial in my knock point to no avail.

I've Decided to put my para-rest (brush rest) back on but have mounted it as low as possible and now the rear contact point is in line with the deepest point of the grip. ( used to be set back and about 1-1/2" off the shelf)
My permarest is an original and when mounted low like this only sits about 1/4" or less above the shelf. I hope this will be a nice compromise that will work for me.

If I can get these shafts dialed in I would like to compare them with tuned 2016 or 1916 and see what feels better.
I'll keep you all posted with my results.

[Dennis La Varenne]

Shawnee,

Could I be so flippant to suggest that you merely increase the head weight on your arrows with no other changes. I suggest a minimum of 160gns and possibly 190gns.

As Grahame Amy points out above, increasing head mass does not change static spine, but does make a huge difference in dynamic spine – the behaviour which your arrow demonstrates in flight.

Increasing your head mass effectively increases your FOC (Forward Of Centre) point which effectively makes that part of your shaft to the rear of the FOC point behave as if it is more flexible – being longer. Your complaint is that your arrows are too stiff.

That ahead of it, being shorter is, by default, stiffer. Those are the influences on the arrow in flight for all practical purposes.

The FOC point acts as a centre of gravity.

The columnar loading on the shaft at loose is dependent upon these factors as Grahame again points out.

The industry spine charts are only meant to be guidelines. Much of their accuracy is lost with your loose technique or how far from centre-shot your bow is for instance. It is a bit harsh to find fault with your dealer on advice given when they cannot possibly factor in your shooting style and the bow you use.

As for bareshaft shooting, I have never had much time for it because I have never seen an occasion where it showed me something I could not solve by using the simple principles above.

Just keep a few field points of differing weights at home to try out. That’s all.

Bareshaft testing has always seemed to me to be an unnecessary amount of cocking around for doubtful result when much simpler means are easily available.

The only beneficial thing I could attribute to bareshaft testing is string nock positioning (possibly) if one has difficulty in understanding the simple principles involved in locating a string nock (not yourself of course).

It is possibly useful for something, but I am not sure what.

[Jeffro]

Shawnee,

Bareshaft testing has always seemed to me to be an unnecessary amount of cocking around for doubtful result when much simpler means are easily available.

The only beneficial thing I could attribute to bareshaft testing is string nock positioning (possibly) if one has difficulty in understanding the simple principles involved in locating a string nock (not yourself of course).

How true,
I feel the same way about that.If your arrows fly straight then that is the end goal. And you can achiece that much easier than doing bareshafting.

[Kanin-maskwa]

Shawnee,

Could I be so flippant to suggest that you merely increase the head weight on your arrows with no other changes.

I understand the need to only make one change at a time however since I was unhappy with my rest position I realize the need to set my bow up the way I'm going to shoot it string and all before I start tuning.

As Grahame Amy points out above, increasing head mass does not change static spine, but does make a huge difference in dynamic spine – the behaviour which your arrow demonstrates in flight.

Increasing your head mass effectively increases your FOC (Forward Of Centre) point which effectively makes that part of your shaft to the rear of the FOC point behave as if it is more flexible – being longer. Your complaint is that your arrows are too stiff.

That ahead of it, being shorter is, by default, stiffer. Those are the influences on the arrow in flight for all practical purposes.

The FOC point acts as a centre of gravity.

The columnar loading on the shaft at loose is dependent upon these factors as Grahame again points out.

Yes I totally get this. When I was fist selecting what I was after I was initially leaning to a quicker arrow and so wanted to shoot 125 gr heads. But now I am happy to use as high FOC as I can get and this goes hand I hand with tuning the arrow by using a much heavier head.

Ideally I would like to end up with around 12 gr/lb FOC >15%
Now will I be happy with the trajectory? I'll find out I guess.

The industry spine charts are only meant to be guidelines. Much of their accuracy is lost with your loose technique or how far from centre-shot your bow is for instance. It is a bit harsh to find fault with your dealer on advice given when they cannot possibly factor in your shooting style and the bow you use.

First in all fairness the archery shop has been accomadating friendly and very nice. However when I first phoned I specifically requested and booked a time to have my bow set up tuned and buy arrows. (since I needed a new string arrows etc)
I brought my bow in and he was very busy he looked over my bow selected a string put the knock point on grabbed some arrows and put the points on shot it once said that's perfect passed it to me I had a shot ( thought to myself mmm seems to kick out but I'm not the expert)
I reiterated how I really want it tuned in good and was told yup that's it she's ready to go those arrows will fly sweet.

Now we had discussed what point weight I wanted and I also had requested feather fletchings but he was a bit busy however when they did not fly right at first he reflected with feathers no problem this helped but does not solve the stiff issue.
Now I have contacted them and they have said they will swap out the arrows if I want. So that's good news.
Since it is quite a ways for me to drive and I have the opportunity to have assistance in tuning these arrows I would like to try that first.

As for bareshaft shooting, I have never had much time for it because I have never seen an occasion where it showed me something I could not solve by using the simple principles above.

Just keep a few field points of differing weights at home to try out. That’s all.

Bareshaft testing has always seemed to me to be an unnecessary amount of cocking around for doubtful result when much simpler means are easily available.

I will be very happy if I get good results from the paper tuning alone. After reading the OL Adcock bareshaft plane method I think it sound good.
I have no problem comprehending tuning theories and the physics of arrow flight etc. My problem is this is the first time I have ever tried to get my bow tuned correctly so have no real first hand experience to know what's going to work for me.

At least I'm learning, and everyone here seems to have insight that is helping me.
Cheers all

[Dennis La Varenne]

Good on you then, Shawnee.

Your shop sounds to be one of the better ones. But as you probably now realise, only YOU can set up your own equipment to the way you shoot. The pro can only get you near it. The rest is up to you.

Nothing about what you asked was in any way the fault of your pro. He did all that he could as you point out. My point was that you sounded a bit ****** off in your post about advice given which could not be in any way the fault of the pro.

I reiterate however my point about not getting too caught up in 'tuning theories'. Our ancestors did very well and shot some remarkable feats without them at all - viz, Howard Hill, Bob Swinehart, Art Young, the Wilhelm brothers to name a few.

With modern technology, we have made shooting more complicated by choice, not by necessity.

It always was simple . . . and still is. It is only in our minds that we have made it more difficult.

Good luck and do well.

[slvrslngr]

Glad they arrived, hope some they are of help. Let us know how you go.

Chris

[Dennis La Varenne]

Shawnee,

Try Chris' heads going up wards progressively. I presume they will be screw-on heads which will make things much easier than glue-on for this sort of thing.

I think you will be very surprised at how easy your 'problems' will sort themselves out just by increasing head mass and forwarding your FOC point thereby.

I will also be surprised if there is any difference in trajectory if at all over the 125 gn heads. That may sound counter-intuitive, but unless you are a long distance shooter well past say 50m on average, you may be surprised at how little difference there is.

It will depend upon how much the heavier heads slow your arrow down, because as you know, the longer the time the arrow is in flight, the greater effect gravity will have on them.

Very few archers realise that a very heavy arrow and a very light arrow travelling at the same starting velocity will have the same trajectory where everything else about the arrow is equal (the Galileo effect).

[Kanin-maskwa]

Well here's an update as to what's happening.
First the fellow didn't show with his paper tuning gear so I just planed tested.

Seems I can get the 145 to group okay but showing a tad stiff and flying crooked. 200Gr points fly straight drop fast and group a bit weak.
I did not have any point weight between these so I'm only guessing that maybe 165-175 grain would be about perfect.
Now the shop I bought my arrows at are keen to rePlace my arrows with 1916's I told him maybe I can get these arrows to tune up but he feels that the 1916 shooting 125 heads would be perfect. So I'll give them a try. I even suggested not taking a full dozen until we get it right but he's confident and said not to worry.

Dennis, I hear what you are saying. I would like to just say one thing though in response to your statement regarding our ancestors etc not getting hung up on tuning etc and doing well.
I have long ago come to realize not to underestimate the knowledge, skill and ingenuity of our forefathers even the so called primitive ones. Im sure there was some form of tuning and it makes me think too that ones like HH had well tuned equipment and were able to get their equipment in to that sweet spot. How else could you consistently hit your mark and consistently group so tightly otherwise?

Anyway back to my arrows. I hope these 1916 with 125 fly well, I hope they will not be too light and Im a Bit worried how they would penetrate. I think they work out to around 9gpp.

I'll let you know what happens next.
Cheers