NationStates Jolt Archive

This is being Draft Roomed to fix many technical problems I wasn't aware would exist.

OOC: You've just given me a very, very nasty idea for a tank!

IC: Alfegos wishes to enquire as to the compatability of this device on armoured platforms, and the amount of space a drum of, say, 10 000 rounds would take up.

While its designed with aircraft in mind there is nothing to stop this weapon from finding a niche in other platforms. Another, heavier version of the weapon is also being designed for ship and ground emplacements.

(OOC: I'm not sure how big of an area a 10,000 round drum would need, but I would estimate it at about no more than the size of a 50 gallon barrel.)

OOC:
A caseless 25mm round for 1250m/s at standard dimensions would weigh 400-500 grams. 10,000 drum would weigh about 6-6.5 tonnes. Really such amount of ammunition won't be exactly a drum. But, anyway, by volume that's about 4 cubic meters. For instance, 1.6 meter diameter, 3 meter long magazine.


Also, note that a caseless weapon at such rate of fire would overheat extremely quickly, so there's no need for large drums. It would only be able to fire in relatively short bursts even on an aircraft. On a tank, the cooling time between bursts would also become very significant. Practical ROF of a caseless 25mm isn't going to be high, even rotary one.

OOC:
A caseless 25mm round for 1250m/s at standard dimensions would weigh 400-500 grams. 10,000 drum would weigh about 6-6.5 tonnes. Really such amount of ammunition won't be exactly a drum. But, anyway, by volume that's about 4 cubic meters. For instance, 1.6 meter diameter, 3 meter long magazine.


Also, note that a caseless weapon at such rate of fire would overheat extremely quickly, so there's no need for large drums. It would only be able to fire in relatively short bursts even on an aircraft. On a tank, the cooling time between bursts would also become very significant. Practical ROF of a caseless 25mm isn't going to be high, even rotary one.

OOC: Thanks for the input Vault, my information on caseless ammo wasn't very good. I had little research time and a couple reguler customers who wanted me to get done as soon as possible, so its sort of a rush job and I spent several failed hours looking for useful info on 25 mm and only got references to the weapons- some of which fire at 8,000 + RPM. Usually when in doubt I draftroom things but this got pushed. Tweek it to perhaps 4,000 RPMs perhaps? This is the start of a series of weapons and in the future I'll try to draftroom those ones but I get very little attention there.

Alfegos Land Systems wishes to procure the rights to produce the weapon, in combination with an armoured fighting vehicle system (Code name: Sun Burst).

(OOC: If you're right about that, then I reckon I could carry at least 20 000 rounds, alongside rounds for a heavy machine-gun...cooling system though would need a bit of work though.)

OOC:
Really if one's going to fire massive amounts of ammunition continuously, cased ammunition works out much better. The chamber overheat with caseless is just too high - instead of the ejected case, all heat is taken by the chamber. Cased rounds are effectively a cooling mass. Besides, on a *tank*, ammo weight isn't a great problem - and caseless only really saves weight, not volume.

Overheat is an issue severe to the point that I, despite using a caseless rifle (R1, you might have heard of it), issue cased ammunition for the light machinegun based on it. IRL, it's the main reason caseless ammo aren't used.

Though caseless ammo in 25mm should hold 50-80 rounds per barrel/chamber before going out due to cookoff and mechanical problems. Less in high-velocity or high-power, though.

OOC:
Really if one's going to fire massive amounts of ammunition continuously, cased ammunition works out much better. The chamber overheat with caseless is just too high - instead of the ejected case, all heat is taken by the chamber. Cased rounds are effectively a cooling mass.
That's an issue severe to the point that I, despite using a caseless rifle (R1, you might have heard of it), issue cased ammunition for the light machinegun based on it. IRL, it's why caseless ammo aren't used.

Though caseless ammo should hold 60-80 rounds per barrel before going to cookoff and mechanical problems.

OOC: Well being a 6 barrel weapon the Cerberus would be able to fire off 360 - 480 rounds before that become a problem, most aircraft won't carry more than 500 and thats the high side for its intended job it seems just fine, being able to fire 360 rounds in less than 20 seconds is advantageous in a dogfight, and the weapon should be cooled down by the time its needed again.

To: Alfegos
SaintB and Tigerlan Weaponry Incorperated has developed this particuler variant of the Cerberus Series for jet engine and rotary combat aircraft and would not recomend it for use on a land vehicle. The soon to come Cerberus 25S and 30S might be more geared for the purpose of land based vehicles.

Right you are... I'll just keep this idea in my mind as something to fall back on if I ever need to.

OOC:

A few points:
Electrical ignition/priming is in no way unique, people have been using it since before ww2 and many cannon roudnscan be adapted to use both mechcanical and electric priming.

Don't bother with a linked feed, beyond 100-150 cannon rounds the weight of the belt and the ammo puts a major strain of the feed mechanism and can cause all sorts of fun issues when udner high G loadings, hence why just about every modern aircraft gun uses a linkless feed.

As for rate of fire the Philco Ford GAU-7 (a 1970s experiemntal 25 CTA/casless rotary that was cancelled as they couldn't get a relaible gas seal) was rated at 6000rpm and the GAU-12 (5 barrel 25mm rotary) has a slectable RoF of 1800-4200.

Wieght wise 102kg is the weight of alight 20mm rotary, a conventioanl 25mm oen would be at 120-130kg and a caseless one probabaly closer to 150kg to account for the better gas seals and heavier chamber structures needed. The length could also do with being upped to about 2.3m.

Finally how is the gun operated I assume a external power source (as in western rotaries) as opposed to a gas operation (russian style).

It would also help if we had more information on the round, I absolutly loath guns with a lonely MV stat esspecailly where custom ammo is involved

OOC:

A few points:
Electrical ignition/priming is in no way unique, people have been using it since before ww2 and many cannon roudnscan be adapted to use both mechcanical and electric priming.

Don't bother with a linked feed, beyond 100-150 cannon rounds the weight of the belt and the ammo puts a major strain of the feed mechanism and can cause all sorts of fun issues when udner high G loadings, hence why just about every modern aircraft gun uses a linkless feed.

As for rate of fire the Philco Ford GAU-7 (a 1970s experiemntal 25 CTA/casless rotary that was cancelled as they couldn't get a relaible gas seal) was rated at 6000rpm and the GAU-12 (5 barrel 25mm rotary) has a slectable RoF of 1800-4200.

Wieght wise 102kg is the weight of alight 20mm rotary, a conventioanl 25mm oen would be at 120-130kg and a caseless one probabaly closer to 150kg to account for the better gas seals and heavier chamber structures needed. The length could also do with being upped to about 2.3m.

Finally how is the gun operated I assume a external power source (as in western rotaries) as opposed to a gas operation (russian style).

It would also help if we had more information on the round, I absolutly loath guns with a lonely MV stat esspecailly where custom ammo is involved

1. It seemed unique enough to NS made weaponry; aside from that it was an attempted selling point by calling it *unique*

2. Linked feed is totally optional.

3. I read about both, my decision for 6,500 RPM was based on those, I actually meant to include that it was up to 6,500 RPM.

4. Another typo... I'm tired, I meant 112 *fixes*

5. This is NS, why couldn't it be fit into a smaller package? A little techwanking now and then don't hurt TOO badly.

6. You assume right, its powered externally by electricity like the firing mechanism.

7. The round is basically a .90 caliber or 25 mm standard.

1. It seemed unique enough to NS made weaponry; aside from that it was an attempted selling point by calling it *unique*

2. Linked feed is totally optional.

3. I read about both, my decision for 6,500 RPM was based on those, I actually meant to include that it was up to 6,500 RPM.

4. Another typo... I'm tired, I meant 112 *fixes*

5. This is NS, why couldn't it be fit into a smaller package? A little techwanking now and then don't hurt TOO badly.

6. You assume right, its powered externally by electricity like the firing mechanism.

7. The round is basically a .90 caliber or 25 mm standard.

1. Since nobody ever actually bothers to mention the priming mechanim it might appear vaguely unique, to be honest in RL it is such an inconsquential issue that it hardly ever gets mentioend outside of saying why the germans had so many different guns and ammo in the classes

2. Linked feed would require a toally different feed assembly and likely a different gun

3. i would bother with more than 1000rpm per barrel esspecially if you are addign a forced air clearance stage

4. 112kg still isn't nearly enough

5. it isn't tech wanking its down to the actual sizes of thing, a 25mm roudn with the perfromance you want is going to warrant a 1.7 to 2.1m barrel plus the length of the chamber plus room for a bit of mechanism behind that.

7. Which again tell us nothing about this actual round: what form factor is it? ie is it telescoped or does the roudn protrud from the front also what type of projectile are you firing APDS, HEI etc etc the reason i don't like lone MV stats is that the MV will differ from one type of round to another and Rl 23-25mm rounds vary hugely. Of course if by 25mm standard you mean 25mm NATO aka 25x137mm KBA then your loads are:
180g HE@1100m/s, 128g APDS@ 1360m/s and 150gFAPDS@1335 (there is also a APFSDS roudn with simialr valeus to the FAPDS, it should be noted that these 2 newer rounds have muzzle energies about 10-20% greater than earlier laodings)

1. Since nobody ever actually bothers to mention the priming mechanim it might appear vaguely unique, to be honest in RL it is such an inconsquential issue that it hardly ever gets mentioend outside of saying why the germans had so many different guns and ammo in the classes

2. Linked feed would require a toally different feed assembly and likely a different gun

3. i would bother with more than 1000rpm per barrel esspecially if you are addign a forced air clearance stage

4. 112kg still isn't nearly enough

5. it isn't tech wanking its down to the actual sizes of thing, a 25mm roudn with the perfromance you want is going to warrant a 1.7 to 2.1m barrel plus the length of the chamber plus room for a bit of mechanism behind that.

7. Which again tell us nothing about this actual round: what form factor is it? ie is it telescoped or does the roudn protrud from the front also what type of projectile are you firing APDS, HEI etc etc the reason i don't like lone MV stats is that the MV will differ from one type of round to another and Rl 23-25mm rounds vary hugely. Of course if by 25mm standard you mean 25mm NATO aka 25x137mm KBA then your loads are:
180g HE@1100m/s, 128g APDS@ 1360m/s and 150gFAPDS@1335 (there is also a APFSDS roudn with simialr valeus to the FAPDS, it should be noted that these 2 newer rounds have muzzle energies about 10-20% greater than earlier laodings)

I usually try to mention the priming/firing mechanism if its not a standard kind. I was trying to point out the low maintenance needed for the weapon and had to explain why.

The Cerberus is an 8 barrel weapon, I never made that very clear and I was in such a hurry I didn't notice. It has a firing rate of 812 rounds per barrel (give or take a .5 in there). I'm sending this whole thing to Draftroom, I thought I was doing pretty good but it seems I have made quite a few mistakes.

112kg isn't enough, you are so totally right.it would weigh at least 20 kg more than a vulcan...

Thats easy, lack of the right knowledge, I'm much better with smaller calibers like 5.56 NATO and stuff.

It was meant to be compatible with any type, the stats are for the regular "ball" munition since its likely to be most used, I'm the kind of guy who just assumes that 25 mm Caseless means NATO standard sizes.