Water Cooled Vickers Guns....

.... are a thing of the past, for a reason. Yes, 
obsolescent technology still abounds. Yes, it is 
possible under some circumstances to imagine 
the re-development of certain technologies. 
Yes, this appeals to the nostalgia of some 
among us for the good ol' days. 

But there are reasons these things have went 
the way of the dodo. They aren't light. They 
aren't easily portable. And they demand fluid, 
which isn't light or portable. And the truth is, 
the capabilities they offer are generally not 
required. 

As has been illustrated by others, the fast, 
sustained fire is not usually a tremendous 
advantage when fighting a modern enemy 
force. They tend not to attack in human waves 
and by clacking away, you'll most likely mark 
yourself out as a target. And your piddly few 
thousand feet of theoretical range won't mean 
much to someone with a missile launcher 
lurking near the horizon. Kaboom, no more Mr. 
Machine Gun. 

Mobility is, in large part, key to survival. 
Fortifications are nice, but they have historically 
had drawbacks which still pertain (psychological 
ones to the force occupying them) and they 
have distinct drawbacks versus support such as 
artillery and air, which can crack bunkers like 
walnuts. And bunkers don't dodge too well. 

Water cooled systems exist on some larger 
combat systems for sea use probably because 
water is something easily access. Some large 
land combat systems may use them, but 
precious few. 

And for the infantry, they are pretty much 
unheard of in modern usage. Why? If I'm going 
to carry 15 lbs. of water, a tripod, and my HMG 
(even with some helpers), that's a lot of weight. 
If I plan to use it for continous fire, that's a 
huge amount of ammo (in fact, one example of 
overuse of ammunition is quite visible in the 
new Bruce Willis film Tears of the Sun - we must 
have missed the off screen supply drop - but 
it's a movie so we suspend disbelief). All of that 
weighs. And as a poor gropos, you're already 
carrying possibly NBC gear, body armour, basic 
combat load, etc. - You're already moving like 
you've got a monkey on your shoulders, and 
the enemies' bullets haven't got noticeably 
slower. 

Most modern squad weapons (and even the 
support det's MGs) tend to fire in bursts at 
targets of opportunity or to suppress rather 
than fully automatic versus a non-existent 
human wave. If we want to apply indirect fire, 
we use mortars. If we want to destroy 
something we really don't like, we use a 
grenade launchers, recoilless rifle, IAVR or an 
ATGM. Or we call for support. 

If a human wave does come, a combination of 
rapid fire from rifles and elevated fire rates 
from support weapons is probably in order, but 
so too is artillery, grenades (rifle and hand) and 
most especially, the old favorite - the Claymore 
mine. And since we're carrying all of this stuff 
around (because it *does* stuff the MG does 
not), adding extra weight to no real gain 
wouldn't make much sense. 

Adding water cooled weapons systems would 
mean an increased demand for logistics (more 
bits than the air cooled versions). Assuming we 
were doing this to let them fire faster/longer, 
we'd eat up more ammo we'd have to carry 
around. We'd also have to hump the coolant 
and recirculation gear. Extra weight very bad.

Where might it make sense to investigate 
modern fluid cooling systems, perhaps using 
water and microtubes or perhaps using 
something like liquid nitrogen?

1) If we had a rugged enough system. 
Radiators tend not to be too rugged. 
2) If we could get good cooling efficiencies 
(might work well if using things other than 
water). 
3) If we could do it in a way that didn't bulk up 
the weapons.
4) If it was someplace the advantage the 
weapon gained was useful (say installed in the 
aforementioned targets.... I mean fixed 
defenses). It might make sense to support 
something like this in a Starship Troopers world 
with swarms of bugs, but I don't think you could 
actually carry enough ammo to win those 
fights...
5. On a vehicle where the added 
complexity/logistics might not matter.
6. PA is debatable. You'll need some water for 
your soldier, but you can't use that. He can't 
drink heated water and water he's drank can't 
be used to cool the weapon. Water he sweats 
out, if you could somehow catch it all, is 
probably near body temperature. And you 
aren't planning to recirc water from the blazing 
hot gunbarrel around inside the suit near the 
wearer were you? I think not. And the weight 
you spend on this cuts down armour, 
electronics, ammunition, sensor systems, or 
movement speed and increases ground 
pressure (an important issue if you don't want 
to get stuck). And of course, the whole point of 
doing this is to be able to fire more.... which 
kind of suggests more ammo yet, also robbing  
your design of further other capabilities. 
You might put something like this on a 
dedicates fire support PA suit, but even that is 
doubtful. 

For most cases, there is just little modern 
justification for this kind of technology for 
infantry arms. For vehicles, it is a debatable 
point, but there could be uses. For PA, in 
restricted cases, perhaps. But by en large, this 
is a thing of the past an should be relegated 
into the same bin of fantasy as steam powered 
tanks or gas powered PA. ;) 

(Which is to say, if it floats your boat, do it.... 
but don't worry too hard about trying to justify 
it on a reality basis.....)

Tomb. 

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Mr. Thomas Barclay
Software Developer & Systems Analyst
thomas.barclay@stargrunt.ca
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