Fat shafts Furious-X, Narrow shafts Nitrous-X.. WHAY????

[SandSquid]

Just finished upgrading my "hunting bow" a camo P3/Magnum/DynaCam to a P3/Elite/Nitrous-X to attempt to get it as close a possible to my "target bow" a P3/Elite/Furious-X


Once I go it tuned and timed I set the weight to 45# and they exactly matched in draw weight. I though it would be interesting to see the difference between them side/by/side through the chronograph with 2 different sets of arrows...

I shot 4 rounds of 6 arrows of each, all readings were +/- 1 FPS

The "fatties": - XRingerHV V1 350 spine, w/ VaneTec 1.75" Fita vanes: 272 grains total:

45# Nitrous-X : 255 FPS
45# Furious-X : 260 FPS


The "pinners" : NanoForce V1 500 Spine w. 4" natural feathers, 254 Grains total:

45# Nitrous-X : 260 FPS
45# Furious-X : 252 FPS

The really odd thing here is I EXPECTED that both bows would shoot the two arrows at relatively similar speeds, but that was not the case...

The narrow and somewhat lighter shafts were 8 FPS faster out of the Nitrous-X bow.
The fatter and somewhat heavier shafts were 5 FPS faster out of the Furious-X.

I'm really baffled, here I thought the Nitrous cam was king of the mountain, but apparently not. the numbers don't lie. Just to make sure I had someone else shoot 6 of each arrows out of each bow, and they came up with the same results.


Is it spine, weight, diameter.... what?

[RogerSr]

I have both of these cam systems, and always thought the Nitrous was the faster of the two, I am surprised! would never have thought.

[Montalaar]

I think that the Nitrous Cams are more sensitive to wrong spines. So if your 'fatties' would have the right spine thry would also be faster with the NOS.

But that is just what i am thinking..

[flytier17]

I agree with Simon. The more agressive energy storage of the Nitrous system puts out more energy than the Furious system. Thus, if the spine of the fat shafts was a little weak to begin with, the added energy output of the NOS system would cause them to act even weaker. The spine could be flexing too aggressively, causing it to drive against the arrow rest. Also, too much of the bows energy is wasted in the oscillation of the arrow. This could attribute the loss of speed.

One more thing to check; remember I told you about putting the wide axle kit on the outside cables to eliminate friction between cables? Do both your bows have the same? Either seperated or touching?

I have a Scepter IV Fury X. It is soon getting upgraded to Nitrous "A" cams. Its setup to shoot 2312's now. I'm gonna record the speed after a bareshaft tune now, and again after I convert to NOS "A's"

Alec

[RogerSr]

I don't think the fatties have a weak spine, it has a 350 spine, and the nanos are 500 spine,

[Montalaar]

Yeah, they are too stiff and this is what is the problem. In my eyes. A perfect spine will result to better results with the NOS-Cam.