RE: Metal Storm

There are a couple of factors that make the barrel lighter. 

1) Unless you are re-loading barrels, it only has to survive 5-30
firings, not the 1000+ that most assault rifles or MG's have to survive
before barrel change, so heat dissipation, metal integrity and barrel
thickness can be manufactured to lower requirements.

2) There is no breechblock or receiver, it's just a tube sealed at one
end.  As each bullet is fired, the propellent squishes the bullet
beneath it, and in a unique technique, the bullet is expanded slightly
forming the base of the firing chamber and consquently sealing the
bullet for the next propellent charge.	Therefore, the back end of the
tube doesn't see the full force of each bullet, probably only force from
the last few closest to the end.  So there is no need for a massive
breech block. 

3) The ammo is already in the tube, it's not fed into it.  Each tube is
pre-loaded with alternating propellent and slug.  So there is no
extraneous weight or mechanism.  A lot of the complexity and mass of
rapid firing systems is the receiver, which has to be designed to keep
the breach sealed, move out of the way to extract a casing, allow a new
round in, ram it home, seal the breech, trigger the firing pin and
repeat.  The mechanism for Metalstorm is: you pull the trigger, an
electrical current flows and propellent explodes - no moving parts other
than the trigger.  

The firing system itself should also be lighter:

My understanding of the firing mechanism is that it is small enough to
be used in a pistol, about the same size as a 9mm.  So a base system
would probably be lighter than the standard rifle, MG, or grenade
launcher of equivalent caliber.  Assuming something like 12v or 24v
required to fire the weapon, each soldier would probably be issued two
sets of rechargeable batteries and some sort of hand generator might
come as part of the structure (i.e. a hand pump like a shotgun) to allow
manual electrical generation.  This is assuming that next generation
uniforms don't include power generators in their boots (saw an article
on a new flexible pizeoelectric matrix installed in running shoes able
to generate a couple of watts) which would allow them to recharge on the
march.

--Binhan

> -----Original Message-----
> From: Ryan Gill [mailto:rmgill@mindspring.com]
> Sent: Thursday, January 17, 2002 8:58 AM
> To: gzg-l@csua.berkeley.edu
> Subject: Re: Metal Storm

<<SNIP>>
> >Remember - there is no brass. No cartridge case. Weight of 
> 20 rounds of
> >a normal weapon is:
> >a)Electromechanical firing system, heavy enough to reliably 
> hit the round
> >with a firing pin plus
> >b)Firing actuator (trigger), safety etc
> >c) Furniture and recoil systems capable of taking the shock.
> >d) 20 cartridges, each able to confine the propellant 
> without ballooning too
> >much.
> >e) A barrel heavy enough to take the heat stress from 1000 
> rounds (say)
> >before deforming.
> >f) 20 lots of propellant
> >g) 20 warheads
> 
> You are still going to have a big slug of metal where your breech is 
> in the back are you not?
> 
> I still think I can more easily carry around 20 rounds of 7.62 in a 
> small box than I can 20 rounds stuck up a tube strapped to my back 
> with a given length barrel. Heck, I can more easily carry around one 
> FAL, a SUIT Scope, and 6 extra  box magazines than I can 7 barrels 
> each with its own train of ammo, a funny mount and spare batteries 
> and 1 scope. (assuming your machine tolerances are perfect every time 
> I change the barrels to the new mount.)