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Old 11-07-2016, 02:39 AM   #271
Icelander
 
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Default Why it would be optimal to be able to use bronze to make firearms

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Originally Posted by Polydamas View Post
Another collection of descriptions of early gunsmithing is Tatterton's book on indian and oriental arms and armour. You will need the other books I suggested for descriptions of gunfounding, since after the very beginning that was mainly a technique for artillery not smallarms. Welding and boring iron gunbarrels was much more efficient in our world.
In our world, bronze was from two to six times more expensive than iron or low-quality steel at the time those guns were being made.

Was the actual labour of welding and boring iron gunbarrels easier than casting bronze ones or was it just more economic because the materials costs were so much lower?

In any case, in my campaign, the short-term economic conditions are such that bronze guns look likely to be much more popular than in real history. Copper is incredibly abundant locally, trade with dwarves and the presence geomancers and of priests of earth deities means that obtaining tin has historically been easier than in our world. Bronze is cheaper than on real Earth. I've been using +2 CF rather than +3 CF and that only because the past fifteen years of civil strife and the past two years of all-out war have driven up the costs of all war materiél.

Not to mention that there has been a very strong cultural preference for bronze in two empires that have been civilised Bronze Age (well, Bronze Age Plus, reaching TL1+3 at one brief flourishing of science and technology) polities for more than three millenia. There are a lot of bronze heirlooms around and the past two years of war have resulted in a truly enormous amount of storerooms and temple basements being emptied out for the war effort, yielding untold tons of bronze weapons and armour.

While the 'modern' mercenary units that do most of the fighting in the Old Empires are usually armed with TL3-4 iron and steel weapons and armoured in mass-produced segmented plate, any self-respecting noble has a retinue clad in ancient (or ancient-looking) bronze armour. A not insignificant part of it is magically hardened to be the equivalent to hardened steel and elites may have orichalum armour, with enchantments of +1 to +3 DR and Hardened being not uncommon.

Assuming that functional bronze can be usefully extracted by melting down ancient bronze gates, temple bells and armaments too badly degraded to be worth using in combat, there are literally thousands of tons of bronze not being used. And since the 'government' of what remains of Free Unther doesn't really have much money, they'll be happy to have at least something valuable to use as part-payment for the foreign mercenaries. This bronze would be available to the PCs at very preferential rates.

Even if this is difficult, there are several hundred tons of copper and tons of tin available to the bronzesmiths and brassfounders of Messemprar and Shussel, surplus from the now-closed mines close by that the guilds and craftsman's collectives have been unwilling to disclose to the ruling factions due to their previous inability to pay in more than promisses. As the PCs have a considerable supply of gold and silver bullion as well as a license to mint their own coinage, they'll be able to buy bronze fairly easily.

The PCs arrived with a navy armed with TL4 mechanical artillery and crossbows and have been buying a lot of TL4 and TL4+1 steel springs from the best armourers and blacksmiths in neighbouring countries. Their soldiers also wear TL4 steel helmets, munition plate, brigandines and mail, so steel and iron are a vital resource for them.

They've already bought so much good steel and contracted with so many of the best master armourers of all the neutral cities that they have contacts in that it is foreseeable that any additional steel and TL4 metalworking will be at a considerable premium. Granted, they will be doing their own TL4+1 steelworking at a colony they are establishing around the captured dragon's lair with the controllable lava flow, but there is a limit to how fast they can expand production from there.

All in all, I expect the fact that making iron and steel barrels relies on the cutting-edge metallurgy and blacksmithing of foreign cities whereas casting bronze guns can be done by adapting methods that have been practised locally for millenia to result in bronze guns being, if anything, cheaper than iron and steel ones, at least for the first few months.

On the other hand, I don't really know how the amount of work per gun barrel compares, with the two methods.
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Old 11-07-2016, 02:49 AM   #272
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Default Re: Emerging smokepowder weapons in my fantasy

Any time one uses welding and boring over casting for economic purposes, it is safe to assume it's material costs that make the difference.

If you have that much bronze readily available for cheap, along with the masses of unskilled laborers, you can get to work on four types of molds for bronze casting on a large scale. Make one mold for your muskets, one for blunderbusses, one for pistols, and one for cannons.

Since gun barrel production will probably exceed the rate at which stocks and firing mechanisms can be made, putting some effort into cannons is probably not a bad idea. After all, I'm sure the navy wouldn't mind a few. That, and the effect a cannonball has when fired through a mass of infantry.
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Old 11-07-2016, 04:01 AM   #273
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Default Re: Emerging smokepowder weapons in my fantasy

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Originally Posted by Nereidalbel View Post
Any time one uses welding and boring over casting for economic purposes, it is safe to assume it's material costs that make the difference.
That is my intuitive feel, but I don't really know enough about smithing to be certain.

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Originally Posted by Nereidalbel View Post
If you have that much bronze readily available for cheap,
I just recalled that a tribe of 'ash'* giants that the PCs have a trading contract with have access to several hundred tons of copper bars, treasure that was their share from a temple that the PCs invaded (and the giants helped them carry away treasure). As these giants are TL0, they'll not have any use for the copper and be willing to trade it away at very good rates for more sheep, goats and various foodstuffs (they like beer).

More tin would have to come from Murghom, where the PCs actually have some contacts, Thay (ditto) or the gold dwarves of the Great Rifts. The dwarves would be the best source, but probably more expensive than the other two. Thay has the benefit of being accessible to the PCs' shipping, whereas Murghom is cut-off from the sea by the enemy empire of Mulhorand, though the Thayan tin mines are pretty far from the ports in question. But there is already infrastructure in place to portage the products of the mines down some rivers to Bezantur, so I imagine that they'll be able to beat the dwarven price easily.

Bronze ought to remain cheaper for the PCs than high-quality steel, at least for the foreseeable future, i.e. the next few months of warfare.

*Really stone giants who live in a strongly volcanic area and happen to have a colouration that is remnisicent of their neighbouring stone.

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Originally Posted by Nereidalbel View Post
along with the masses of unskilled laborers, you can get to work on four types of molds for bronze casting on a large scale.
How much use are actual unskilled labourers?

Well, I suppose many of the 'unskilled labourers' available are actually skilled acricultural workers displaced from their homes. Not to mention all the (more-or-less former) slaves, rural and urban, who fled the invaders rather than accept temple slavery among the conquerors and have ended up in the massive refugee camps around the last great city of Unther. A significant portion of the slaves will have experience of public works, in the off seasons for acricultural work.

On the other hand, with a hundred or so professional bronzesmiths, brassfounders and suchlike available, I imagine that there won't be much call for actual unskilled labour near the casting of the barrels. Though if there is anything that people without Bronzesmith, Machinist and/or Metallurgy at 12+ can usefully contribute, obviously, it would be nice to be able to employ some of the refugees.

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Originally Posted by Nereidalbel View Post
Make one mold for your muskets, one for blunderbusses, one for pistols, and one for cannons.
I'm pretty sure that they'll end up with far more moulds than that.

They already have calivers of ca 22-bore with a 24" long barrel, so there will be an institutional tendency among the officers assigned to the ordnance and procurement duties to buy more of those. Experience has shown that even with very long sword bayonets, however, the calivers are not as effective in a melee as good spears purposely designed for two-handed use, at least not if the other side has lances or spears of more than 6' total length.

The Artisan Guards, recruited from the para-military security regiments that grew up in the quarter of Messemprar reserved for craftsmen during the last fifteen years of effective anarchy, use staves for riot control and many of their number are adept at the fighting arts of the Qarradu sarrupim azamrutu (Warriors of the Argent Lance)*, albeit a simplified version. The Artisan Guards will be used as security for various urban locations and as a military police unit. During training with firearms their officers expressed a desire that they might be issued something better balanced for use as a fighting staff than the short caliver. I expect that to lead to a slender fusil with a longer barrel than the calivers.

There are also excellent reasons to contemplate specific weapons for ST 11+ recruits, as heavier weapons firing larger balls than the 22-bore calivers are not only more effective against heavily armoured infantry, but they also have a longer point blank range and may thus be able to fire effective volleys at long enough range to make harassing fire with slings or bows ineffective.**

Then there are carbines for cavalry or mounted infantry, horse pistols for cavalry (don't need to be as carefully made as Sea Service pistols which must resist sea spray) and maybe even mobile artillery to support the infantry. And that's just the smoothbores for land. On sea, there are calivers for marines, blunderbusses, pistols, murderers and swivel-guns.

*As the formerly apolitical mages and scholars of the Northern Wizards found themselves cast as an armed resistance against the God-King of Unther and later as the effective defenders of the free city of Messemprar as authority in Unther crumbled, those among its ranks who rose to the occasion as battle mages form a strong faction within the organisation, as sort of brotherhood within a brotherhood. Their mastery of spells relying on pure magical force has been combined with local armed and pankration traditions to create an all-around martial art focusing on using magical staves and wands as melee weapons, often enough enhanced by blades of magical force. Many patrotic citizens, even if they are not able to cast spells, have adopted the techniques of spear, staff and baton/long knife fighting of these mystical knights.
**Realistically, bows and slings are only useful for harassing fire at an area at distances over 50 yards or so and they are never very effective against armoured troops, but it is nevertheless extremely annoying to calivermen to have skirmishing archers and slingers at 150-200 yds raining down arrows or sling bullets which can cause painful wounds, put out eyes or even kill occasionally. With a 22-bore smoothbore, it's useless to fire at point targets at that range, because the trajectory is too extreme and the shooter needs to know the exact range, but heavier muskets might reach 200 yds without having to fire at too much of an angle.


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Originally Posted by Nereidalbel View Post
Since gun barrel production will probably exceed the rate at which stocks and firing mechanisms can be made, putting some effort into cannons is probably not a bad idea. After all, I'm sure the navy wouldn't mind a few. That, and the effect a cannonball has when fired through a mass of infantry.
Cannon need firing mechanisms, just as smallarms do, although I imagine that being so much more expensive than fusils, the PCs will opt to make all the cannon they buy 'magelocks', i.e. fired through an Ignite Fire enchantment and powered by either an Exclusive Powerstone or the Power 1 enchantment*.

Cannons also require carriages where metal is used for such things as axles, screws, trunnions and quoins. This makes them a lot more trouble to construct than just wooden stocks, I imagine.

That is not to say that some of the casting capability won't go toward artillery, just that this will be because of their military utility, not because it's faster to make cannon than fusils.

Cannon round shot is actually not very effective against personnel, at least not compared to the 2-3 lbs. of smokepowder it takes to fire it and how many ca one ounce round balls might be fired from fusils for the same amount of powder.

The navy will, however, be very willing to receive half-pounder to 3-pounder swivel-guns and the smaller 'murderers'**, which are not only useful as anti-boarding defences when loaded with grapeshot or canister, but will also serve to discourage attacking dragons and other flying monsters.

*With a limitation I'll allow on the enchantment cost for only working with one specific spell, by analogy from Dedicated and Exclusive Powerstones. Power 1 which can provide 1 FP to power six different spells, some of them Always On, is a lot more useful than Power 1 which only powers one spell.
**Long muskets with claws to support against walls, firing 4 oz. lead round balls.
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Old 11-07-2016, 06:42 AM   #274
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Default Re: Emerging smokepowder weapons in my fantasy

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Originally Posted by Icelander View Post
Cannon need firing mechanisms, just as smallarms do, although I imagine that being so much more expensive than fusils, the PCs will opt to make all the cannon they buy 'magelocks', i.e. fired through an Ignite Fire enchantment and powered by either an Exclusive Powerstone or the Power 1 enchantment*.

Cannons also require carriages where metal is used for such things as axles, screws, trunnions and quoins. This makes them a lot more trouble to construct than just wooden stocks, I imagine.

Cannon round shot is actually not very effective against personnel, at least not compared to the 2-3 lbs. of smokepowder it takes to fire it and how many ca one ounce round balls might be fired from fusils for the same amount of powder.
The firing mechanism for a cannon is actually rather simple compared to a rifle, which is why cannons hit the fields before muskets. The hard part is getting your metal strong enough to survive the require pressures, and I'm sure your smiths and mages can handle that with ease. As for mobility, well, fixed emplacements on walls just plain scare people, while those on ships only need to move enough to handle their own recoil. And as for not being effective against infantry? Check out some statistics from the American Civil War. The Napoleon Model 1857 could fire solid shot, shotgun-like shot, and explosives at a range of 1,619 yards. Solid shot ended up taking more than a few soldiers out of the fight when they saw it rolling along and thought they could kick it, while fragmentation rounds are just plain bad for everybody.
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Old 11-07-2016, 11:55 AM   #275
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Default Re: Why it would be optimal to be able to use bronze to make firearms

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In our world, bronze was from two to six times more expensive than iron or low-quality steel at the time those guns were being made.

Was the actual labour of welding and boring iron gunbarrels easier than casting bronze ones or was it just more economic because the materials costs were so much lower?
That is the kind of question which would take real research to answer (Tatterton just describes four or five methods of making and finishing gun barrels which were all used in South Asia between the 16th century and the 19th ... he is not interested in the economics, and the smiths who made the guns lacked the concepts).

Casting long thin-walled things, like a sword blade or musket barrel, is difficult because the bronze cools as it flows through the mould and bits of coal from the crucible can get stuck as the mould narrows. In the case of gun barrels, you would also have to get rid of the core (I think for great artillery they sometimes used a wooden core and burned it out, but I have no idea what they settled on by Gribeauval's day). If they still made a few brass-barrelled pistols or blunderbusses in the 18th century, someone may have described the process (check Diderot's Encyclopédie), but again the workers and shop owners did not necessarily have the education and numeracy to analyse the economics of their business. This is long before Taylorism.
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Old 11-07-2016, 07:13 PM   #276
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Default Re: Emerging smokepowder weapons in my fantasy

Regarding casting barrels for cannons, wasn't sand used as an advancement over clay cores or something? Or am I thinking of something else?
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Old 11-08-2016, 01:55 AM   #277
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Default Re: Emerging smokepowder weapons in my fantasy

And just to make it clear ... I will happily give advice on where to start research (and double check against sources which are within my apartment or online). But I won't donate the sheer amount of money and skilled labour which would be required to give even a half-assed answer to your questions. This is an area where I just have general ideas and some knowledge of where to find the details.
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Old 03-11-2018, 08:20 AM   #278
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Default Magico-alchemical ignition

One PC is receiving a set of magical pocket pistols in a 'deringer' style, made out of orichalum with double barrels 3" long. The grip of one of pistol is made from shark's tooth and the grip of the other from mother of pearl. The former pistol is decorated with engravings of the PC defeating divine emissaries of their enemies and defending his men from sharks in the ocean and the other pistol has him fighting beside sahuagin (shark men) against the nobles, priests and generals of the other side.

The weapons carry various enchantments, but the ones I'd like to get help with are the ones that ignite the smokepowder and are meant to get the most of the propellant in a short barrel.

Pulling the trigger activates an Essential Air spell to fill the barrel with the essence of oxygen and ensure rapid burning of the propellant and simultaneously causes the 3 FP version of the Ignite Fire spell to go off in the entire barrel, the equivalent of a blowtorch being applied to the 25 grains of finely-ground REF 0.8 smokepowder (about mid-way in REF between high-quality black powder and TL6 smokeless powder). A Shape Air spell ensures optimum mixing of the burning propallant and the Essential Air while the combustion is going on.

This propels a 10mm 90 grain lead and antinomy ball out the barrel. The orichalum construction means that there is no risk of catastrophic overpressure despite the near instant detonation of the smokepowder. I figure that it could use a larger powder charge, but as it's so tiny and the grip only allows three fingers, we want to avoid too much of a kick.

I can use Doug Cole's spreadsheet to find the stats, but I need to know what would be reasonable in terms of PSI, burn length and, derived from that, the muzzle velocity.

What would be a reasonable figure for muzzle velocity? 1,200 fps? 1,500 fps? 2,000 fps? 3,000 fps?
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Old 03-11-2018, 09:42 AM   #279
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Default Re: Emerging smokepowder weapons in my fantasy

1,200 fps at most. That's the velocity of a .45 Long Colt black powder cartridge, which has Rcl 4 in a much larger and probably heavier handgun, according to High-Tech p94. Trying to use more power than that in a tiny gun is likely to result in it flying out of the user's hand.
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Old 03-11-2018, 10:53 AM   #280
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Default Re: Emerging smokepowder weapons in my fantasy

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1,200 fps at most. That's the velocity of a .45 Long Colt black powder cartridge, which has Rcl 4 in a much larger and probably heavier handgun, according to High-Tech p94. Trying to use more power than that in a tiny gun is likely to result in it flying out of the user's hand.
Even if this thing had double the velocity of the .45 Long Colt, it would still have much less momentum and therefore less recoil impulse. It's a 90 grain ball vs. 230 to 255 grain one.

The .45 Long Colt is also black powder, whereas this is using magical smokepowder which has 60% more REF for its volume. Black powder revolvers are not particularly efficient, wasting propellant energy because the cylinder seal is not perfect. As the barrel of the magical 'deringer' is a smoothbore orichalum tube with no moving parts or any need for a seal (it's a muzzle loader where the charge is ignited magically), ideally, almost all the energy generated should go toward accelerating the ball

And with Essential Air, Shape Air and Ignite Fire, the entire charge should ignite nearly instantly and with very high efficiency, accelerating the projectile to a much higher velocity than REF 0.5 black powder would.

I'm looking to benchmark quite how fast. I'm leaning toward anywhere from 1,500-2,000 fps.

If it got 1,600 fps, the recoil impulse would be about equivalent to standard pressure 9x19mm Parabellum ammunition.
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