Aluminum/carbon spines

[Gem=)]

I shoot a Evloution 2 bow, 68 inch, 30 pound bow. i have been shooting with 1716 easton jazz arrows for over a year now (they are my very first set of arrows) then my dad lent me 4 of his 3-04/680 Easton ACC arrows (he shoots a winstar bow, 68 inch, 38 pound bow). any way i used them and i scored really well (nothing outside the gold (well 3 times i got outside the gold)) and my groups became tighter!!! so i thought wow, i will ask for some of these for christmas or my birthday (which is less than a month after christmas).

any way my question is, what would there be any difference if i used the correct spine size for the weight of my bow? and if it does what spine size would be best for my bow?

Gemma

[its my party and]

Originally Posted by Gem=)

I shoot a Evloution 2 bow, 68 inch, 30 pound bow. i have been shooting with 1716 easton jazz arrows for over a year now (they are my very first set of arrows) then my dad lent me 4 of his 3-04/680 Easton ACC arrows (he shoots a winstar bow, 68 inch, 38 pound bow). any way i used them and i scored really well (nothing outside the gold (well 3 times i got outside the gold)) and my groups became tighter!!! so i thought wow, i will ask for some of these for christmas or my birthday (which is less than a month after christmas).

any way my question is, what would there be any difference if i used the correct spine size for the weight of my bow? and if it does what spine size would be best for my bow?

Gemma

Whats your draw length Gem?

[Gem=)]

about 27 1/2 inch

[Kae]

Carbon/aluminnium spine matching is something of a dark art, and the easton charts are only a guideline.

This information is really needed before any sort of spine can be calculated:

1 - Exact draw weight at your draw length
2 - Your exact draw length
3 - Longrod (Do you use one?)
4 - Type of limbs & Riser
5 - String details


All of this may sound like overkill, but I can guarantee all of the above factors make a difference to the spine that you need.
Recurve is much harder to spine for than compounds. However, a set of arrows too stiff are better than a spine that is too weak, as you can still tune a slightly stiff set, but you can't a weak one.

The difference you would notice would be depending on how well you shoot. A decently matched set of arrows will group better, improve sight marks and generally improve scores.

Hope some of this helps,

Kae.

[madmac]

I shoot a revolution(back on it hurrah) ,I pull 42 lbs my arrows are acc 3-04 and they are 27.5 " and are suited to me .These arrows could be a bit stiff but you can get away with stiffer arrows. Its a case of try them out again and see how you shoot again and if you are happy go for it but if in doubt speak to nearby archery shop.

[tgross144]

I use arrows that are one spine size weaker than the Easton archery chart suggests. I am using redline carbon arrows. The arrows can be forced to work whether they are stiff or weak. It's just a lot more work if they are weak.
If it is possible get the material that the string is made from, exact draw length, exact weight of bow at your draw. These are key to getting the proper arrows.

Ask your father and friends for some advise as well. I'm certain that one of them has a vast store of archery knowledge.

Good luck,
Tim

[napolienne]

Gemma, do your 1716s tune properly? If so, the closest matches spine wise in ACCS are the 2-04 (slightly weaker) and the 3x-04 (slightly stiffer). See the easton spine/weight comparison chart here. I always recommend this chart as the best place to start when buying new carbons, as the selection charts are at best a guideline, at worst downright wrong.

edit: forgot to add how to use the chart - find where your ali is on it, then draw a horizontal line to the left from that point. The carbon nearest the line is the closest match - underneath the line means stiffer than the ali (less deflection), above the line means weaker (more deflection).

[Jerry Tee]

There are few other things to consider other than static spine. The speed or cast of the limbs, the weight of the shaft and the weight of the point. The faster a pair of limbs can push the arrow for a given poundage the more the arrow will bend and thus appear to be weak. The arrow bends becasue it has inertia(The back of the arrow wants to go faster than the front.). There fore the lighter the arrow the less inertia and less bend.Point weight adds to the inertia of the front of the of the arrow only. this will make the front of the arrow more difficult to accelerate and will therefore make the arrow bend more, so appearing to be weaker.There other factors, in general any thing that adds weight to the back of the arrow makes it act stiffer. Anything that makes the arrow go faster makes it appear weaker. The tab and loose can have a bearing but hopefully they will stay constant.
Your present arrows may look as if they fly well but that does not mean that they are tuned for your bow. I would take the fletches off one of your arrows and do a bear shaft check at around 20yds. (Down load and read the Easton tuning guide.) If your present arrows are matched to your bow then the fletched arrows and bear shaft will hit the target at the same point. This will give you an indication as to your starting point as far as for spine selection goes. (the more information you give to the person who is selling you the arrows the more likely you are to get the right arrow) If you can get away with it do the same with the one of the ACC's. This will give you a very good indicator if you are going to buy the same type of arrow. It will come out too stiff but how much too stiff will help determin the point weight arrow combination that suits you best.
As for your question( sorry put the cart before the horse ). Any bow that launches the arrow straight and true wil be more accurate than a bow that does not.

[hooktonboy]

Originally Posted by madmac

I shoot a revolution(back on it hurrah.........

Slightly off topic BUT - glad you've picked that revolution back up madmac. Aint they nice?! Are you going to buy a 2006 model (no lumps!)?

Sorry Gemma, hijacked your thread for a mo! I'm on a 27" draw with just on 30lb(well I'm only little!), D75 string, etc etc . I find 1000 spine Ok with a 60 grain point, but 840s with a 90 grain point work just as well. I think the heavier point makes them act weaker. Bit of a dark art though and, for such an important bit of kit, very hard to"try before you buy" - shame.

[glynhenry]

Originally Posted by Gem=)

I shoot a Evloution 2 bow, 68 inch, 30 pound bow. i have been shooting with 1716 easton jazz arrows for over a year now (they are my very first set of arrows) then my dad lent me 4 of his 3-04/680 Easton ACC arrows (he shoots a winstar bow, 68 inch, 38 pound bow). any way i used them and i scored really well (nothing outside the gold (well 3 times i got outside the gold)) and my groups became tighter!!! so i thought wow, i will ask for some of these for christmas or my birthday (which is less than a month after christmas).

any way my question is, what would there be any difference if i used the correct spine size for the weight of my bow? and if it does what spine size would be best for my bow?

Gemma

3-04 are very much stiffer than 1716. If 1716 is the correct spine for you then the equivalent in ACC is 2-04. Really need to check your draw length and draw weight to check correct spine. 2-04 will give you a 10% weight gain over 3-04 and thus a good improvement on your sight mark.
Glynhenry