Liquip Propellent Gun

[Fengxi Zhou]

From Fengxi Zhou <fen...@prancer.eche.ualberta.ca>

Can anyone on the net enlighten us on the pros and cons of a liquid propellent
gun? Almost all guns are fired by solid explosives. I understand GE or FMC is
studying the possibility of liquid fired guns. Reportedly, it has higher
muzzle velocity and the ammo storage is more compact. Before firing, you
feed a projectile and then inject the liquid explosive, other than that, it
fires pretty normally.

Questions:
1. Why higher muzzle velocity than solid gun?

2. How about rapid firing? (2 step loading!)

3. Any disadvantages compared to solid propellent guns?

Thanks in advance.

--
Fengxi Zhou
fen...@prancer.eche.ualberta.ca

Who said nothing is impossible? I have done nothing through the years.
-- Anonymous

[Arno Hahma]

From aha...@utu.fi (Arno Hahma)

In article <C0E5K...@law7.DaytonOH.NCR.COM> Fengxi Zhou <fen...@prancer.eche.ualberta.ca> writes:

>gun? Almost all guns are fired by solid explosives. I understand GE or FMC is
>studying the possibility of liquid fired guns. Reportedly, it has higher

That is right, many companies study such guns. GE already has working
models, if not already in production/field use. Rheinmetall is
planning to get one into production soon.

>Questions:
>1. Why higher muzzle velocity than solid gun?

Because you can adjust the pressure-time history of the firing. Just
adjust the propellant feed and try to maintain a constant pressure in
the tube. That is _very_ hard to do with solid propellants - the
Germans tried it during the WW2 with little success (V-3
"Hochdruckspumpe", planning to shoot some 200 km from France to
London).

In addition, the liquid propellant has a higher specific impulse than
the solid propellants. The liquid propellant is much less erosive than
high energy powders (lower combustion temperature). All of these give
rise to a better performance.

>2. How about rapid firing? (2 step loading!)

No problem, as the propellant is fed with pumps. Load the ammo, close
the breech and fire, just like before. Pumping the propellant is done
very fast, there is a small initial volume and additional propellant
is fed during combustion, like in a diesel engine. This is usually
done using the gas pressure in the tube.

>3. Any disadvantages compared to solid propellent guns?

Yes: much more expensive. Both the gun and the propellant. It has been
estimated, that the liquid propellant costs about 10 times more than
the present solid propellants. Still, the liquid propellant gives so
many advantages, that it is considered cheaper (easy transport, storage
and waste disposal, no cartridges, no factories for loading the
cartridges, far safer and less vulnerable, etc).

>Fengxi Zhou
>fen...@prancer.eche.ualberta.ca

ArNO
2