Rifling spin rate question - tiberius first strike paintball

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ALIHISGREAT
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Sun Nov 15, 2009 9:43 am

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Hi guys, haven't posted on here for a while, but i thought some of you may be able to help me with this question...

So i was just wondering what spin rate would be needed to stabilize the First strike rounds as pictured above in order to prove that it is not plausable and i thought some of you may have the know how to work out a rough esitmate for me.

I will try and find the weight of the round but i have a feeling it is around 3g

Thanks.
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Ragnarok
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Sun Nov 15, 2009 10:07 am

ALIHISGREAT wrote:So i was just wondering what spin rate would be needed to stabilize the First strike rounds as pictured above
No spin at all. They're drag stabilised by a hollow "foster" tail.

However, rifling serves two purposes. Stability and "averaging out" imperfection.

In this case, the fins may cause the latter.

That is, if the round is imperfect, and has drag that would veer it to one side if unspun - if you spin it, then rather than just veering off, that "veering" is averaged in all directions and causes it to travel in a little spiral (not perfect, but at least it's heading in the right direction, rather than off on a road to nowhere.)

The question here is whether the "fins/rifling" impart enough spin (if any at all) to meaningfully perform this averaging.
That I can't tell you. I'd really need to experiment with them (and I'm not paying the exorbitant prices) or see high speed footage of them in flight.

(That said, they're essentially FN303 projectiles for paintball. The military designers probably had a little idea what they were doing.)
Does that thing kinda look like a big cat to you?
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VH_man
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Sun Nov 15, 2009 10:12 am

ah, I have seen these.

I think they would spin a little bit due to the angled "fins" on the back of the foster tail, but I dont think its going to help much with your accuracy.

I saw a demonstration of these and saw that they are actually more accurate than I thought. Think a High-end air-soft sniper rifle.

I will surely pick up a few of these, as a future project of mine is to construct a bolt-action paintball gun and these would make perfect "sniper" ammo.
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Ragnarok
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Sun Nov 15, 2009 10:23 am

VH_man wrote:I will surely pick up a few of these, as a future project of mine is to construct a bolt-action paintball gun and these would make perfect "sniper" ammo.
They're gorram expensive (something like $0.75 a shot). I'd sooner recommend making paper rings to glue to the back of regular paintballs as tails - it would replicate most of the effect at a fraction of the cost.
Does that thing kinda look like a big cat to you?
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Sun Nov 15, 2009 10:56 am

hectmarr wrote:You have to make many weapons, because this field is long and short life
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Solar
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Sun Nov 15, 2009 3:59 pm

I just fired the FN version at Nellis AFB a few weeks ago. From 100ft I was able to hit the test target every shot. What is funny is that every shot dropped in to what would essentially be a crotch shot. The audience got a chuckle out of that one.

I have met Tyler Tiberius a few times and when asked about maximum accurate distance, he responded "depends how high you turn up the pressure". The fins are designed to spin stabilize the round. They are completely gel instead of being half made of plastic.
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ALIHISGREAT
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Sun Nov 15, 2009 3:59 pm

I know that the fins drag stabalize it, i was just wondering how fast it would have to be spun to get a greater degree of accuracy.
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Sun Nov 15, 2009 4:54 pm

I am not sure the spin rate, but most paintball fields allow up to 300fps and the FN less lethal are fired at 400fps. I am sure the fins are maximized for those velocities.
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Ragnarok
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Sun Nov 15, 2009 6:05 pm

ALIHISGREAT wrote:I was just wondering how fast it would have to be spun to get a greater degree of accuracy.
If you're firing an otherwise stable round, it doesn't need to spin very fast at all to see accuracy gains. It can be as leisurely as a turn in many feet.
Does that thing kinda look like a big cat to you?
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