Re: Rail guns (was: US SOCOM desires...)

[Kenneth Mølbæk \(basis\) <kennethm@xxxxxxxxxxxx>]

> Kenneth: I've cleaned up your English some.  No offense--I understand
> English isn't your native language--but it makes it far easier for us to
> read.>

True and tanks. I will try too improve. Or get my posts corrected.   
 

> > But doesn't this mean that, with equal training, a low-power
> > optic gives you an edge?
> 
> Not necessarily--see my sidebar about the Navy's experience with laser
> sights.  Low-power optics are useful in certain situations, yes, but they
> aren't going to revolutionize warfare the way self-contained cartridges, the
> Maxim gun, etc., did.

True and I did. But optical sights aren't lasers, there is no mesmerising dots here. And if you keep the magnification low, you can actually have a wider field of vision then in an iron sight. Or at least this is true for the bag up iron sight, I have used.  
On the other hand I think it is safe to say, that in the world of sporting- and hunting rifles you choose your sight in accord with your passion, - or purse. And in the world of military hardware: you use what you are issued.
Of course the discussion of one against the other is valid any way. But as with most questions of passion or taste, we are not likely ever to agree.     

> If all the valid tech trouble raised here were to be solved, we'd have
> man-portable particle accelerators.  That may sound like a flip statement,
> and it sort of is.  The point is, though, that sure, *anything* can be done
> assuming a high enough level of technology exists.  If you're going to
> assume we have tremendously energetic and compact power sources, plus room
> temperature superconductors, plus this, that and the other, then you can do
> a hell of a lot.
 
> Personally, I prefer to stick to either our current tech level, or what may
> be reasonable in the next ten years.

 Valid point. It was just a thought. - A dead thought apparently.

> > If you have two bullets with equal energy the smaller calibre will
> > have the best armour penetration, Simply because it has to make
> > the smallest hole. It of course also helps to be very pointy.
> 
> Not true.  The determining factors in armour penetration are sectional
> density and velocity.  At equal energies, the round with the higher SD will
> tend to penetrate more.  Sectional density is found by dividing the bullet
> mass by its cross-sectional area.

Ok. This point was not raised in the article I have read. But it makes sense for projectiles with the same velocity. But the energy is equal to the square of the velocity. So to compare  2 deferent sized projectiles with same kinetic energy. You must invent at new concept of sectional momentum. Or how concentrated is the energy. With the highest concentration, that is the smallest projectile, penetrate the farthest.  This of course hinges on the assumption of equal energy and no deformation. 

> Re: pointed noses.  During WW2, a field expedient antitank round was made by
> removing the spitzer from an 8mm Mauser cartridge and reseating it,
> reversed, in the cartridge.  For some reason, wadcutters or blunt-nosed
> rounds tend to have better penetration than pointed rounds.

Well I meant in soft armour, for some bazaar reason I just didn't write it. But this refers too the same article, so please comment.
An explanation could be that a blunt-nosed round isn't deflected as easily as an ordinary round against a hard surface. Or else it could be that a sloped round hits with the entire surface of the slope. Meaning that a given molecule of metal travels from the point of round and op against the entire slop. Which would give a dramatic increase in friction. I can suddenly understand why it's a hole science too invent new ammunitions.       
These 2 reasons don't sabotage my point about soft body armour. Since once the Kevlar is penetrated, it dos not require much energy to push aside. It is a woven structure after all.        

         
Kenneth