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Author Topic: Dark matter.  (Read 10148 times)

Offline lightarrow

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Dark matter.
« Reply #25 on: 09/03/2007 11:58:32 »
I should think a mini black hole with the mass of a bullet would be rather difficult to use as it would have a very short life!
With the mass of a normal bullet would be meaningless; the higher accuracy is given just by its extremely higher mass (and so momentum) because almost nothing could make it change its trajectory or slow it down. This is the reason they use big calibers for very long range shooting (50 BMG, for example).
Mass gives range, and impact, but not accuracy.  You will probably get better accuracy (at least in close range) from a .22 high velocity than you would from a higher mass at lower velocity
Try to send a .22 10 km away. Why do you think a tank's cannon has a much greater range of shooting than a rifle?
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(again, density also matters, and in particular, the cross sectional area, as this will effect aerodynamic losses).  If you want the best of both worlds, you want to aim for high mass, small calibre, high velocity, high spin rate.
Yes.
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The 50BMG is high calibre not for range but for impact (it is intended as an anti-vehicle weapon that is intended to have a higher impact than is normal for antipersonnel weapons).
Not only for this, also for snipers.
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A bullet with the mass of a black hole would be of microscopic dimensions, and so will have very little air resistance (ofcourse, you may wish to encase it in a sabot in order to obtain any reasonable gas pressure behind it within the gun barrel).
Of course. Would it be less dangerous than Uranium? Brrrrr! ;)
 

another_someone

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Dark matter.
« Reply #26 on: 09/03/2007 17:22:45 »
With the mass of a normal bullet would be meaningless; the higher accuracy is given just by its extremely higher mass (and so momentum) because almost nothing could make it change its trajectory or slow it down. This is the reason they use big calibers for very long range shooting (50 BMG, for example).
Mass gives range, and impact, but not accuracy.  You will probably get better accuracy (at least in close range) from a .22 high velocity than you would from a higher mass at lower velocity
Try to send a .22 10 km away. Why do you think a tank's cannon has a much greater range of shooting than a rifle?

But, I did acknowledge that mass gave range, but tank artillery is not highly accurate (when you are blowing a hold in the ground a few feat across, you don't care if you are 1 inch off target).  Even more interestingly is that tank mounted canons are often smooth bore rather than being rifled, which clearly demonstrates that high precision accuracy is not the primary objective.

The point is that long rang, high calibre, artillery has a highly parabolic trajectory (with proper computer calculation, you can give a fairly accurate estaimate of what the shell will hit, but it is not as simple as looking down a rifle sight and assuming a flat trajectory).
 

Offline lightarrow

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Dark matter.
« Reply #27 on: 09/03/2007 19:06:54 »
Try to send a .22 10 km away. Why do you think a tank's cannon has a much greater range of shooting than a rifle?
But, I did acknowledge that mass gave range, but tank artillery is not highly accurate (when you are blowing a hold in the ground a few feat across, you don't care if you are 1 inch off target).  Even more interestingly is that tank mounted canons are often smooth bore rather than being rifled, which clearly demonstrates that high precision accuracy is not the primary objective.
The point is that long rang, high calibre, artillery has a highly parabolic trajectory (with proper computer calculation, you can give a fairly accurate estaimate of what the shell will hit, but it is not as simple as looking down a rifle sight and assuming a flat trajectory).
Yes. I only intended to say that, if you want a sniper rifle for very long range shooting, you cannot take a .22 caliber(*), even if you design it in the better way is possible; you have to take bigger calibers. To avoid bring with himself ≈ 15 kg of rifle, in the case of BMG, they are studying other calibers, like 416 Cheyenne Tactical and similar.

(*)Here I mean a "normal" rifle. Nothing prevent to use a .22 caliber with a much longer than usual bullet (and so, heavier) in a futuristic rifle, one day. They should find a way to give enough force to such a little sectional area bullet.
 

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Dark matter.
« Reply #27 on: 09/03/2007 19:06:54 »

 

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