NationStates Jolt Archive

WORK-IN-PROGRESS

http://img.photobucket.com/albums/v293/grunt74/NS1/gackack.jpg
Over 100 billion dollars of research funding went into this special request rotary artillery piece. The gun itself uses a revolutionary belt fed loading system and rotary barrels to fire rounds extremely rapidly, at 90 rounds per minute sustianed, but the top cyclic ROF is classified. A fuel cell/ battery system powers the rotating action, or it can be hooked up to a vehicle engine/battery system.

Towed Versions |

M204A1: 4 155mm Barrels = $1.8 million
M204A2: 3 200mm Barrels = $2.3 million
M204A3: 4 105mm Barrels = $1.3 million



Self-Propelled Version |
M-204: 4 155mm Barrels = $6 million

Stats(Mobile Version)
M-204Mobile Gatling Artillery
The M204 features at least 25mm of carbon composite encased depleted uranium armor all around. Armored bulkheads separate the crew compartment from the ammo and fuel tanks The top panels of the vehicle (100mm thick) are also designed to blow outwards in the event of penetration by a HEAT projectile. Unlike tanks, this vehicle is not designed to take frontal hits, but instead the heavier armor is on the top where the biggest threat is (from enemy artillery and anti-tank missiles) It is protected against nuclear, biological and chemical (NBC) warfare as usual. The 200mm cannon holds 100 rounds in an automatic belt fed loadingsystem. An extra 120+ rounds can be stored externally or extra rounds can be stored in a follow on ammuniton vehicle. Also if a helicopter comes upon an un-escorted M204 it will be met by a .50 cal MG, 20mm Vulcan gun and stinger missiles. The 20mm gun is alsoeffective against lightly armored vehicles when used with DU shells.
Specifications
Power Plant: Two PD XM-1800 Diesel-Electric Hybrid with fuel cell battery backup.
Maximum Speed: 45mph
Weapons
(1) 4 barrel 155mm Cannon
(1) 12.7mm (.50 cal) M135 Gatling Gun
(1) 20mm Vlucan Gun
(12) FIM-92 Stinger
(1) L718 smoke/tear gas generator
Crew: 5
Electronics
Thermal Imaging System (TIS)
Eyesafe Laser Rangefinder(ELRF)
Digital fire control computer
Thermal/Nightvison/Video Gun sight
Tactial LAN
UHF, VHF,SATCOM communications systems
GPS reciever
*all electronics are shielded from emp in faraday cages.
Price
$6 million

You got a firing rate from a normal 155mm artillery piece to compare it with?

IIRC the real life M109 Paladin 155mm Mobile artillery has a maximum rate of fire of 6 rounds per minute, I have not calculated a reasonable ROF fr the M204 yet

WIP=Work in progress
this is not done yet.

You spent 100 billion dollars on an artillery unit when you could have easily taken a more trustworthy model and modified it until you think it is right. That would have worked.

Wasn't my money, I was paid to design this :)

Hope your selling it later on, would be interested in buying some.

Wasn't my money, I was paid to design this :)

And soaked up an enourmous amount of cash in the process?

Nicely done.

And soaked up an enourmous amount of cash in the process?

Nicely done.
shhhhhhhhhh ;)

for sale now

A rof of 90 would destroy the barrels quickly. Even divided between four barrels, thats 22.5 rounds a minute. No 155mm artillery alone can do that, what makes you think this one can do 3-4 times what other ones do?

It is an issue of loading

Indeed, and you are under the mistaken impression that you can increase the rate of fire just by increasing the barrels. You can't. Increasing the barrels only serves to facilitate higher rate of fire by reducing heating issues and barrel wear. You still have to have a single loading mechanism capable of pulling it off.
The problem is that you can't fit a loading system that good on a vehicle chassis. You'd be hard pressed to do that well on a ship (contemporary ship-based systems still only fire 15 rpm), and you can't possibly scale it down to a ground vehicle.

It's bigger than 2 large main battle tanks
its just a scaled up belt fed machine gun

15 x 4 = 60 so 60 rpm would be better?

It also seems that accuracy, which is key with arty, would be a problem. 90rpms from an artillery gun, and you'd probably hit everything except what you were aiming for.

Fire for effect

It's a gun version of the MLRS, meant for area target saturation

You ever watch how long the recoil is on an artillery gun? If it wasn't that long it would pulverize itself or kick itself out of position. Also worrisome is the heat buildup in the barrels prematurely triggering shells; you could actually be dealing with a cookoff or worse yet detonation before the breech closes. I'd advocate powerful water cooling. You might consider making it recoilless but that nearly doubles ammo weight.

I'm not saying rapid fire cannons are impossible, but they will require a different approach. I personally have a system that compresses and flash detonates a reactive gas to propel lower caliber(never above 100mm) projectiles to incredibly high speeds. The recoil is absorbed by the mass of the piston used to compress said gas, and cooling is achieved by a counter-cylinder vacuuming the gas out(increasing its volume etc.). Also important is the suppressor(yes thats right) that reduces recoil and prevents muzzle flash, which must be continuously drained of water vapor. (No one steal any of this, its a personal invention, clunky as it may be.)

God help your men if they want to have one shell land even remotely close to another.

Pics are cool though.

Ahha but the recoil is what operates the loading system!

Um, if you want to mount a rotary arty gun you'd need a significantly beefier mounting than those tiddly little piston-things in the picture...

mind you, it is only an artist's conception, not a technical drawing ;)

1) As I said, rate of fire is an issue of the mechanism rather than the number of barrels. Just increasing the number of barrels doesn't necessarily increase rate of fire.

2) 15 rpm is for naval guns (they could probably do higher, but that's a realistic rate). They are much larger and heavier than comparable land-based systems due to lack of size and weight limitations. And the better loading systems that can be provided allow for simpler, less complex handling cartridges. The limit for land-based guns is about 12 rpm burst (very short duration) due to those limitations. Now, if you use the fixed cartridges that you'd have to, you will have some issues with range, specifically, a rather high minimum range and a lack of versatility. Range will be determined solely by barrel length (unless you want to alternate charges, which will cause even more accuracy and ammunition problems). The most notable things here are that it will actually be rather easy to get under these guns, especially for fast vehicles, and they can't have the versatility of modern gun/howitzers.

3) Taking into account barrel life, ammunition, and what not, I would say that the maximum shouldn't be more than 25 rpm for the 200mm weapon, 50 rpm for the 155mm weapon, and 60 rpm for the 105mm weapon. Also note that this thing is going to run out of ammunition very quickly. We're talking maybe 2 - 3 minutes to empty its entire load, and reloading will be a nightmare. The ability to accept ammunition directly fron external sources will help, but that's a double-edged sword (see 6)

4) Belt fed is all well and good, but remember that leaves very little choice in ammunition type, as you already have the specific order fixed. That might come back to haunt you as you find insufficient amounts of a needed ammunition type, or almost as bad, wasting dozens of rounds just to get off a few of the type you need.

5) With the size of the carriage needed for such a weapon, and everything else getting stuck in, it is not going to be speeding along at 45 mph. 35 mph is a little more realistic.

6) This weapon will take some time to set up and displace, and with its size, it may be rather vulnerable to counterbattery fire. It's also plagued by vulnerable moving parts that are easy to damage. A penetrating hit isn't needed if a bit of shapnel finds its way into the mechanism, or worse, the exposed ammunition (you said it could be fired from exterbally stored ammo, which means the feed is outside and not really protected.

7) As mentioned by others. Accuracy is quite important with artillery. This will be too wildly inaccurate for many applications, including destruction of key targets and close support. Its only value is high-volume bombardment of large formations and installations. This is not similar to an MLRS, which is actually quite accurate and capable of hitting spot targets. A better comparison would be the BM-21 Grad. Like that unit, you will have to be using several units to saturate an area if you want to hit something.

8) Very big logistical tail. Each of these will need the logistics support of at least 4 normal self-propelled guns. That's a heck of a lot, so a battalion for 18-24 155mm guns will only be able to have 4-6 of these.

9) This is not very good strategically. I doubt many players have bothered to make railways designed for over twice the standard gauge, and you'd be pretty hard pressed to build a HETS that could do hold it. Similarly, few aircraft, real or fictional, would have the capability to carry it due to weight and dimensions. All this means moving this over any real distance will be a genuine nightmare.

10) Finally, cost. This is going to be expensive. The gun alone should be costing several million (I'd say $4 million for the 155mm, $5 million for the 200mm, and $3 million for the 105mm). A towed version might cost $1-2 million extra with options like the ability to traverse and an APU. When you account for the size and complexity of the vehicle mounting it (and the features), a full self-propelled version should be in the range of $15+ million (gun mounted externally on large chassis a la M107, M110, and 2S7 - note that only elevation could be changed, with little or no real traverse), or up to $20 million with the gun actually integrated into the vehicle and 180 or possibly 360 degree traverse.

noted, a few points:
I didn't conceive of this, I was given a very vague request and I did my best at interpreting it. I have no idea how it's supposed to or is going to be used, other then its to be basically a rapid fire artillery cannon which can provide MLRS type wide area suppressive fire.(not supposed to be very accurate)
The reason for the high rate of fire is not the 4 barrels, the 4 barrels are only to make sure that itl doesn't melt after a few rapid fire shots. I figured the the loading system ( belt fed, recoil-operated) combined with the rotating barrels (which are electricly turned) would allow for a high rate of fire. As I said eariler I don't have my heart set on 90 rounds per minute thats just something I pulled out of my ass.
On the ammuniton types, I have no idea how to load conventional assortment of arty rounds as fast as the belt fed system, which is why you would most likely have 3 boxes each of different ammuniton types, and of course you would have an ammunition resupply vehicle nearby. Reloading is as simple as sliding a new ammo box over and linking the new belt to the old belt which is already being fed into the gun.
The main focus of this project is the towed version, the mobile version is more of a token unit that was designed with the leftover funds. All towed emplacements are vulnerable to counterbattery fire....and if a enemy artillery shell lands near say a regular 105mm cannon, theres going to be a big mess either way(stored rounds, personnel, vehicles )


I will take your concerns...... into consideration, considering all the considerition that you've shown :)

Really, its a pretty useless system anyways. You could get a large number of towed artillery for cheaper, who could collectively fire as fast. Similarly, you could get vehicles like the giat Caesar, which for 6 million could buy you 12(or a collective 76 rof), as well as accuracy and a fast, mobile carriage, as well as being able to choose what ammo every fire.

Not nessecairaly hitting at you, just saying it isn't the most efficient use of money.

Forgot to mention:
Reloading is not simple, and will involve a crane system. The ammunition here is way too heavy to manhandle. That's also going to be a limiting factor on rate of fire, depending on the belt length. You have to either sacrifice versatility, or sacrifice real rate of fire.