Antarctic Space Nazis Across the Multiverse

[johndallman]

Originally Posted by Icelander

First of all, how much more time and resources would it take to make SAPHE and APHEX rounds in heavy rifle, machine gun and autocannon calibers, compared to ordinary ball or AP rounds?

Could they have brought tools to manufacture such ammunition and fuzing for it, or is that complex enough to require a much larger society?

OK, let's talk about ammunition manufacture in general at first. The ASN are in a different position from a modern hand-loader, or a post-apocalypse survivor, in that they need to manufacture ammunition. While they will undoubtedly recycle all the cases and bullets that they can manage, they need to be able to use guns on a large scale without fatally depleting their stocks and becoming vulnerable.

So we need to look at the tooling and skills needed for that. Materials are a separate issue, for another posting.

To make cartridge cases and bullet jackets on any scale, you need to do deep drawing of brass or steel. This needs power-operated machinery. It doesn't take all that much skill to operate, but it wears out the dies that the metal is forced into fairly quickly. So you need skilled metalworkers, good steel and plenty of gauges and cross-checking to keep replacing those dies.

You also need ovens for annealing the cases/jackets at several stages in the drawing processes, and those need quite precise temperature control. They were usually heated by coal gas in wartime Germany.

The big machines that a full-scale ammunition factory uses for drawing tens of cases at the same time are just too big for your 400lb/item transport limit. Take the plans and hope to build them in a few years, but you need smaller machines for your immediate use.

The best place to get those will be the experimental shop at a large armaments firm, and that's where you can also get operators, tool and die makers, and all their specialised tools and equipment. So that will get you machines that are good for any small arms calibre, maybe up to 12.5mm. If you want to cope with 20mm, you'll need an extra set of machines, probably from a different factory's experimental shop.

However, you'll only get annealing ovens that dismantle into 400lb pieces if you're very lucky. They aren't built to be portable or dismantlable, since they're mostly made of firebricks. So take the metal and glass parts, plus the temperature sensors and control systems, and build new ovens in your industrial area. If you have to transport firebricks for the first few, OK, but brick-making of various kinds is an industry you'll want to set up early on. It's an easy one to forget, because its products are so cheap and ubiquitous from TL4 onwards.

tooling to make 7.92x94mm AP ammunition for the Panzerbüchse 39 more or less dropped in their lap in 1943. Assuming that could be disassembled and transported in pieces which individually are no larger than 400 lbs.

The tooling will be the dies, gauges, precise alloys and annealing specifications, and so on. You'll need a set of drawing machines and annealing ovens to use with it, which we've accounted for above, and assembly tools, which come soon.

You need to set up your drawing machines, and they need power, probably hydraulic, since small movements with great force come naturally to that. Well, until you can set up a factory-level hydraulic power system, which demands a lot of good-quality metal pipe, you're going to need a small pump for each machine, and something to drive it, which may well be beast-power. Easier to get those designed and built in Germany than in a colony. And you need lubrication for the machines, which may well be tallow, and hydraulic oil, which won't be. Better take plenty of that along.

You've got your bullet jackets and cartridge cases. Now you need fillings for them. For plain ball ammunition, the filling is lead, and the weight needs to be fairly precise for accuracy. That's normally done by drawing lead wire to size, cutting lengths, which is easy to do accurately, and ramming it into the jackets with hydraulic power. So you need lead mining, smelting, another set of machinery from a lead wire supply company, or to have a smaller set designed and built in Germany, and time and tools on the drawing presses for filling the jackets.

WWII Germany had some alternative bullet materials, for 9mm Parabellum, either a bullet made of sintered iron powder, or a solid iron bullet coated in lead. Sadly, neither is likely to work well in rifles: at rifle speeds, the rifling will rip up the bullet surfaces and the bullets will go wild.

I found that the Mauser 1918 Tank Gewehr / Mauser T-Gewehr in 13.2 TUF / 13x92mmSR was designed and built extremely quickly in WWI

That was easy to do when you had a fully-functioning arms industry, with access to all the materials, workshops and skilled people you needed. It's going to be a bit harder in the ASN's situation.

I have no idea whether making the ammunition would be a massive undertaking or a comparatively simple modification of assembly lines that already make smaller rounds.

Ah, assembly. You can't take the big machines that assemble lots of cartridges in parallel apart into 400lb chunks. They're bigger than that. The low-tech fallback is hand-assembly, which needs only reloader's tools, but isn't something you want to entrust to slaves, given the ease of over- or under-loading cartridges.

You probably want to get some small machines built in Germany for use until you can build a proper production line. Making them capable of handling large rounds is quite possible, given they're a custom job, but may well mean that they're less capable of handing a lot of smaller rounds at once. The German answer is to have modular machines, or more than one type of machine, but this all takes time, which is not in long or readily predictable supply for the planned departure.

I know that the Germans issued Soviet AT rifles … no idea how hard it would be to set up a manufacturing line for such ammo at the Last Redoubt.

Not that hard if you planned for it, but quite hard as a late improvisation.

Depending on how hard it is to make SAPHE rounds ...

There are two major difficulties:

The first is fusing. Getting HE rounds to detonate when they're supposed to, but not otherwise, is fiddly with WWII technology. The usual way is to have an impact fuse with a short delay built in, which is armed by the centrifugal force applied to the shell when it's spun by the rifling. This has to fit in a 20mm round and leave space for some explosive. It's lots more small parts to make, machine tools to make them, production lines to run, and so on.

The second is assembly, which is unavoidably more dangerous given you're putting high explosives into the shells. If ammunition assembly is being done by hand, it's quite dangerous, and if it's being done by machine, there's a risk to hard-to-replace machinery.

So I think the pragmatic answer is not to make HE ammunition until the population and industry have been built up significantly. Take the designs and samples with you, but you're going to have to re-create the manufacturing processes because people will have forgotten the details by the time you're ready.

[Icelander]

Wow, johndallman, that's exactly the kind of analysis I love seeing!

I'll have to get to answering it later, as a player surprisingly found himself available and we're playing a session tonight.

Time to decide on the size, power source, TL, armament and capability of that ASN Year 51 scout zeppelin in the Dreamlands. It's meant for exploration, not conquest, so it really doesn't need to carry much weight beyond supplies for the crew and fuel, if any, but I'd really like it if it could cruise for a few days, at least, with longer cruises being awesome, if possible.

It should also be fairly compact, as airships go. Basically, the highest tech concept they can manage, aided with RPM rituals, packed into the smallest possible package, designed to be transportable through gates which are not infinite in size. After all, making gates bigger is a massive megaproject and one not done until after exploration has confirmed whether a world is worth it.

Nuclear? Not nuclear?

And using just 7.92x57mm weapons or with a wider selection of possible weapons?

Do they have SAPHE ammunition by Year 51?

[adm]

Have you considered using semi-ridged, or blimps for these small scouting units, instead of zeppelins?

[AlexanderHowl]

Dirigibles are also really difficult to make. You need silk for the fabric, aluminium for the frame, and hydrogen for buoyancy, each of which needs a complex infrastructure to create. Nuclear powered dirigibles are even worse, as you need uranium mining, boron production, control rod production, and fuel rod production. It requires a population of around a minimum of 10,000 experts to even maintain the infrastructure for one nuclear power plant, though each additional plant requires much less to due to efficiencies of scaling (for example, the UK civilian nuclear energy program only employs around 15,000 people).

[Icelander]

Originally Posted by adm

Have you considered using semi-ridged, or blimps for these small scouting units, instead of zeppelins?

Yes.

I imagine that the first airships they used were of such kinds. Indeed, I am not sure at what point they would be able to upgrade to 'proper' zeppelins, but more or less guessed that by Year 51, with a population of over four million, a system of allegiances on Germania Hyperborea, trade links with 25 million allies on another world and resource-gathering operations on several other worlds, their economy has advanced sufficiently to allow them quite advanced airships in comparison with their earliest forays.

[johndallman]

Originally Posted by Icelander

Nuclear? Not nuclear?

And using just 7.92x57mm weapons or with a wider selection of possible weapons?

Do they have SAPHE ammunition by Year 51?

Well, if they have a population of four million, with all the men working on military, political, scientific and engineering jobs, and they haven't had a civil war due to typical Nazi factionalism, they should have SAPHE and effective mass-production of military goods.

On the nuclear front, RPM has the potential to save a great deal of effort, if you're willing to have that. You're opening a Pandora's Box if you do so, but you may be happy with the idea. Simply allow Matter effects to separate U-235 from other uranium isotopes, with vastly less cost and equipment than doing it by mundane means. With highly-enriched uranium, you can build small high-powered reactors: that's what submarine reactors use.

You can also build simple nuclear weapons really easily, which is what you may want to avoid.

[johndallman]

Originally Posted by Icelander

… I am not sure at what point they would be able to upgrade to 'proper' zeppelins, but more or less guessed that by Year 51, with a population of over four million, a system of allegiances on Germania Hyperborea, trade links with 25 million allies on another world and resource-gathering operations on several other worlds, their economy has advanced sufficiently to allow them quite advanced airships in comparison with their earliest forays.

Yes, they can build large rigid airships. Those may not be the right choice for exploring vessels with small crews. Since most of the weight of a rigid airship is in the skeleton and skin, they have the best lift-to-weight ratio if they're the classic shape, with a length-to-diameter ratio somewhere between 4:1 and 8:1. That makes them inconveniently portly for going through limited-size worldgates. Can I propose a mad-science alternative?

The gas in these airships will be hydrogen, because helium is rare. Hydrogen is pretty cheap. Have an airship with wheels under its gondola, capable of being transported deflated. Open relatively small gates, establish local control on the far side, wheel the airship through, inflate it and set off.

[adm]

Originally Posted by johndallman

Y...The gas in these airships will be hydrogen, because helium is rare. Hydrogen is pretty cheap. Have an airship with wheels under its gondola, capable of being transported deflated. Open relatively small gates, establish local control on the far side, wheel the airship through, inflate it and set off.

This was the idea I failed to specify above.

If you are using magic for resource harvesting, Helium may be much easier to produce.

[Icelander]

Originally Posted by johndallman

Yes, they can build large rigid airships. Those may not be the right choice for exploring vessels with small crews. Since most of the weight of a rigid airship is in the skeleton and skin, they have the best lift-to-weight ratio if they're the classic shape, with a length-to-diameter ratio somewhere between 4:1 and 8:1. That makes them inconveniently portly for going through limited-size worldgates. Can I propose a mad-science alternative?

The gas in these airships will be hydrogen, because helium is rare. Hydrogen is pretty cheap. Have an airship with wheels under its gondola, capable of being transported deflated. Open relatively small gates, establish local control on the far side, wheel the airship through, inflate it and set off.

That's a very good point.

Although the World Tree almost never allows paths that are easy to wheel anything over, which is why they had to make yeti carry stuff along it and couldn't just use wheelbarrows or even drive trucks through.

But they could move it through the gate this way and then inflate it when traversing the World Tree, flying 'above' it (up and down are a bit complicated around the World Tree).

[Icelander]

Originally Posted by johndallman

The gas in these airships will be hydrogen, because helium is rare. Hydrogen is pretty cheap. Have an airship with wheels under its gondola, capable of being transported deflated. Open relatively small gates, establish local control on the far side, wheel the airship through, inflate it and set off.

Originally Posted by adm

This was the idea I failed to specify above.

If you are using magic for resource harvesting, Helium may be much easier to produce.

The earliest ASN airships used coal gas, but they've used hydrogen for at least a generation now. According to the 1632 series community, manufacturing hydrogen is not particularly complicated once you have achieved mature TL5 / early TL6 (to hazard a GURPS guess for their approximate TL in that series).