Adding 200 grains to carbon arrow?

[D. Devall]

Hi guys. I've been away for a long while, but recently got the big again, and happened into a good deal on a bow from a friend. It's a Hummingbird RD longbow, drawing 58@28, and I draw 29.5.

The dozen new carbon arrows that came with the bow are properly spined, as far as I can tell, having not bare shafted them. They don't seem to wobble in flight and don't show any pronounced nock right or left on target. But, with 100 gr screw in point, fletched and with nock, only weigh 380 gr total. In order to get anywhere close to the often recommended 10 GPP, I'd need to add about 200 grains to the things.

Is it advisable or even possible to just stick an additional 200 gr to the point end of the arrow? How should I deal with this issue? I don't want to damage by bow by shooting super light arrows.

Oh, the current shafts are Carbon Impact Hunter + XLT 6000 and according to their chart may be a bit under spined already. Hmm.

Thanks in advance. I'm Beyond excited to finally own a bow again!

[JimB]

Are you saying they weigh 380 grs with point installed?Define properly spined.There has to be some tuning involved to determine point weight.What point weight did your friend shoot?Need more information.

To be able to add 200gr to the front end of the arrow, you are going to have to go to (at least) the next stiffer spine shaft. If the arrow is properly spined, and you add 200gr to the front, you will make the dynamic spine too weak to work off of that bow.

Bisch

[D. Devall]

JimB, my mistake. Edited in more info.

Bisch, that was my fear. I'd like to avoid the expense of setting up new arrows, but I certainly don't want to end up with something inconsistent or unsafe by trying to make these work.

There is a possible way that the arrows you have might work, and that would be to be able to cut enough length off to stiffen them up enough to accomodate the extra 200gr up front. With you having a 29.5"DL, it is unlikely that you have the extra length to cut off though.

And I would be scared as heck every time I let the string go with a just over 6gpp arrow!!!

Bisch

[D. Devall]

Originally posted by Bisch:


And I would be scared as heck every time I let the string go with a just over 6gpp arrow!!!

Bisch

That's no joke. It hadn't occurred to me to even weigh the arrows till this eavening. Luckily I didn't shoot it all that many times like that.

And I don't believe there is enough shaft there to shorten it any significant amount.

How about the full length weight tubes or the old rope or weed eater line that some folks shove inside the shaft? Is this a legitimate way to do things? Or am I better off just setting it aside and waiting to do things properly with a new set of shafts?

Weight tubes are an option. The heaviest ones I know of are 8gpi, so you could get your 200gr that way. You will have to deal with nocks coming out on hard hits, or glue in your nocks, but that option would be waaaaay cheaper than new arrows, and might just be worth a try.

Bisch

[TOEJAMMER]

If you go with Bisch's info re. the 8gpi weight tubes, they will work.  To keep your nock from blowing out and yet still be able to remove them, use the glue stick that is normally used for gluing paper etc.  Use it on the weight tube when you insert them and on the knock.  It will dry and hold them tight yet you will still be able to remove them should you so desire.

[D. Devall]

Thanks gentlemen.

For the time being, I tried paracord. (I'm impatient and like to tinker)

Cut and trimmed the cord to be a little more than double the length of my arrow, removed nock and point, threaded a piece of floss down through the insert and out of the nock end, tied that to the middle of the paracord with a loose knot, pulled the doubled cord up through the shaft then a good tug removed the floss. Scrunched the rest of it down and reinstalled the nock.

I now have 3 arrows that weigh 525 +/- 1 gr with a 100 gr field point installed. FOC is only about 8% but tmrw I will try to find 200 gr points locally. That should get my weight and FOC right and will just had to shoot it to see how spine and arrow flight is affected. It may fail catastrophically but hey, it may work!

[kbetts]

100 grain brass insert......?  The length of the insert is going to help keep the spine up.

I can tell you with a pretty high degree of certainty that there is little to no way a straight 100 grain point spines properly out of that bow.  Sounds like a trad bow set up by a wheel bow shop.

[The Whittler]

Your XLT 6000 arrows I would think are a 600 spine which are way under spine. You might be pulling around 62#-63#. You may need a 400 spine arrow. Good luck.

[Rob DiStefano]

Originally posted by The Whittler:
Your XLT 6000 arrows I would think are a 600 spine which are way under spine. You might be pulling around 62#-63#. You may need a 400 spine arrow. Good luck.

agreed - absolutely too light a dynamic spine.  with your draw length and holding weight it'll take 400's to stabilize and not be so close to dry firing.

and adding front end weight to an already unstable arrow will further decrease the dynamic spine stiffness.

I had never heard of those shafts, but went on the OP's saying that he thought they were "properly spoined". If they are indeed .600 spine, they are waaaaaaaaaaaaay underspined!

Bisch

[D. Devall]

Definitely under spined. With the added weight from the paracord they are much more visible in flight and are impacting the target VERY nock left.

Looks like I've got no choice but new arrows. Thanks guys!

[JimB]

I'm convinced that 6000 does not equate to .600 spine.Their site doesn't give deflection,that I can find but 5000 shafts are lighter than 6500 shafts,so the number means nothing.

7.9 grs is not that light a shaft weight.My guess is those may be .400 deflection.I would stay away from weight tubes and similar if at all possible.I have played with them a lot and all are a pain in many ways.They stiffen dynamic spine,regardless of how soft the material is.They also lower FOC.

I would be looking very closely to make sure you aren't getting a false weak indication.If they are .400,with 100 gr heads and paracord,that's a possibility.

At any rate,whichever shaft you choose,I would want to end up with points heavier than 100,as this would vastly limit your choice in broadheads and heavier heads would be stronger.

[BowHunterGA]

I am currently shooting carbons with just over 400 grains up front. You have to tune and be meticulous but it is possible and works very well. I am not a fan of "weight tubes" but when I do need more weight I will add 1/4" rope inside the shafts. Quiet, consistent, does not affect arrow flight and won't knock your nocks out.

[BowHunterGA]

I am currently shooting carbons with just over 400 grains up front. You have to tune and be meticulous but it is possible and works very well. I am not a fan of "weight tubes" but when I do need more weight I will add 1/4" rope inside the shafts. Quiet, consistent, does not affect arrow flight and won't knock your nocks out.

[Doc Nock]

To stiffen a weak spine one can shim out the side plate to take up weakness...

One guy recommended electrician tape...build it up till it works well, then peel it off and measure the thickness and just add the dimension behind the side plate material...