Question about spine specifications???

MilDotMaster · 01-07-2006, 10:22 PM

I just noticed that Easton Arrowshas there .340 spinedeflection at 28 inches of arrow length; whereas, GoldTip lists their .340 spinedeflection at 32 inches of arrow length. Doesn't that mean that the GoldTips have a stiffer .340 spine arrow? HELP! Longer arrow with the same deflection ofthe shorter arrow mean stiffer to me, right?

I wish all arrow manufactures would rate their products at the same length and same deflection specifications, so we can compare apples to apples. Please explain to me why this is or if I have it wrong.

ewolf · 01-08-2006, 07:11 AM

Yes, the gold tip would be stiffer since it has the same deflection at a longer length. 28" is standard throughtout the industry.

Paul L Mohr · 01-08-2006, 10:46 AM

Ok, my first question would be where did you hear that they measure spine at 32 inches on gold tip arrows? I always thought this was an AMO regulated thing so that it was accurate from arrow to arrow. If they are doing it differently that would be one more reason not to buy them for me. And it would be odd that many complian about them being on the weak side if this were really case.

Are you going by the arrow lengths listed on thier site, or did you acually read somewhere that that they measure spine this way? Some of their arrows only come in 30 inch lengths, it would be pretty hard to measure the spine at 32 inches if the arrow wasn't that long. Not to mention the arrow would have to be longer than 32 inches in order to measure it that way. If you are going by the lengths listed under the arrows on thier site this just tells the length the raw shaft comes in for that size arrow. This is not the length they measure spine at. Weaker spine arrows usually come in shorter overall lengths becaue they will not be used in longer draw bows, why waste material if you don't need too. However it is suggested that you cut an inch or so from both ends of the shaft because they are more consistant and straighter towards the middle of the shaft.

I just did some searching on some of JeffB's and others posts regarding arrow spine and gold tips. I could find no mention of gold tips being measured differently than any other brand, and the spines seem to be in order with every other manufacturer. Other than not being really consistant with cheaper arrows.

Find someone with OnTarget or TAP and they could tell exactly what spine an arrow was at what length. I have both but they are expired and I can't afford to buy them. I don't think they measure goldtips at 32 inches though, I think I would remember reading about that if it were the case.

Paul

MilDotMaster · 01-08-2006, 07:50 PM

This is what info I had off of their web sight. So your saying this is just shaft length, not the length that the spine was tested? Thanks for clarifying that, I wasn't sure. I would love to know what the spine of this arrow or the .340 spine Easton Super Slims would be at 29.5 inches. I'm right on the edge to needing a .300 spine arrow which puts me way over 520 grains total arrow weight. I'm trying to stay within the .340 spine and have my arrow weight at 440-475 grains. If they are all tested at 28 inches then that makes it worse for me. That means the .340 spine arrow at 29.5 inches would be softer than expected. Correct?

Tech Specs

Weight
9.7 gr / in.
Spine .340"
O.D. .300"
I.D. .246"
Length 32"

bigbulls · 01-08-2006, 08:21 PM

That just means that the raw shaft length is 32 inches long before you cut it to your desired length.

The spine deflection is still measured at the center of a 28 inch span on the shaft.

MilDotMaster · 01-08-2006, 08:50 PM

Quote:

ORIGINAL: bigbulls

That just means that the raw shaft length is 32 inches long before you cut it to your desired length.

The spine deflection is still measured at the center of a 28 inch span on the shaft.

Thanks for the help.

Rick James · 01-09-2006, 06:41 AM

Quote:

ORIGINAL: MilDotMaster

This is what info I had off of their web sight. So your saying this is just shaft length, not the length that the spine was tested? Thanks for clarifying that, I wasn't sure. I would love to know what the spine of this arrow or the .340 spine Easton Super Slims would be at 29.5 inches. I'm right on the edge to needing a .300 spine arrow which puts me way over 520 grains total arrow weight. I'm trying to stay within the .340 spine and have my arrow weight at 440-475 grains. If they are all tested at 28 inches then that makes it worse for me. That means the .340 spine arrow at 29.5 inches would be softer than expected. Correct?

Tech Specs

Weight
9.7 gr / in.
Spine .340"
O.D. .300"
I.D. .246"
Length 32"

I have the newest version of OnTarget2 at home, I will post up how these spine for you later.

MilDotMaster · 01-09-2006, 09:55 AM

Rick,

that would be great!!! Thank you very much.

Here are some specifications:

31 inch draw length plus loop

arrows are 29.5 inches due to QAD rest being set back. I may be able to get away with 29 inch arrows.

.340 spine arrow preferred. Easton Super Slims or Gold TipPro Hunter 7595's.

100 grain tips

4 inch VaneTech vanes at 29 grains

Nock is either 9 grains for easton or 12 grains for GT

65 pound draw weight, may go up higher if spine of arrow will allow.

2006 Old Glory with speed cams installed. 36 3/4 inchaxle to axle and 8 inch brace height.

If you need any other info let me know.

Note: the software I'm using moves me into a .300 spine arrow as soon as I move the bow up to 67 pounds draw force. That tells me I'm over-working the .340 spine arrows at 65 pounds draw force and that may not even take the speed cams into consideration. I may be setting up the software wrong because I'm not sure how to use the over-draw function or if that function matters to me since my arrows are cut back below my draw length.

Thanks for your help! Looking forward to seeing the results.