Emerging smokepowder weapons in my fantasy

[Icelander]

Glass glans fragmentation grenade; Dmg 3d [1d+1] cr ex; Weight 1 lb; Cost $60

A simple weapon made from an ovoid glass container, the size that in LT can hold a maximum of 14 cubic inches (but designed for less volume than that), with Rugged and Expensive modifiers applied to represent high-quality and good design, as well as another +4 CF* for standardisation and quality control. Comes to 0.384 lbs. of casing, which costs $12. Add 3.5 oz. of smokepowder (0.22 lbs. and $44) and stuff the rest of the volume full of bronze fragmentation material (just under 0.4 lbs., $4).

More or less the density of rock and will fly as far as a standard 1-lb rock.

Glass glans flame grenade; Dmg 1d burn cyclic (10d turns); Weight 1 lb; Cost $115

This is a large glass ovoid container, the size of the glass heavy fragmentation grenade, but with thinner walls. It's strengthened with thin lead bands at the ends and holds 14 cubic inches of Alchemist's Fire. A direct hit inflicts the above damage (as well as splash damage of 1d-2 burn to anyone within one yard in the second of impact and 1d-4 burn to anyone approaching that close while the flame still burns). If thrown on the ground, it instead creates a circle of flame 2 yds wide, doing 1d-1 burn to anyone within 1 yd and 1d-2 burn out to 2 yds from the point of impact. In either case, it burns for 10d seconds. Non-sealed armour protects at 1/5 DR and water cannot exstinguish the fires.

It's about as dense as a fired clay projectile for slings and will fly as far as 1-lb clay ovoid.

Glass glans heavy fragmentation grenade; Dmg 4d [2d+2] cr ex; Weight 3 lb; Cost $130

A simple weapon made from an ovoid glass container, the size that in LT can hold a maximum of 14 cubic inches, with Rugged and Expensive modifiers applied to represent high-quality and good design, as well as another +4 CF* for standardisation and quality control. Reinforced +200% for thicker sides. Comes to 1.152 lbs. of casing, which costs $15. Add 8 oz. of smokepowder (0.5 lbs. and $100) and stuff the rest of the volume full of bronze fragmentation material (just under 1.35 lbs., $13.5). Round to a neat $130.

Denser than rock, but not as dense as lead. Gets a +20% bonus to Range and a +1/die bonus to damage compared to rock ammunition.

*Less than the x10 to base cost applied to the smallest earthenware container used as a shell, because glass was actually used in alchemical work and suchlike, so would be more familiar with precise requirements and odd shapes.

[Varyon]

Originally Posted by Icelander

3-lb Fragmentation shell; Dmg 6d [4d] cr ex; Weight 3 lbs.; Cost $350.

Packing a casing of the same size as the 2-lb and 2.5lb shells to maximum capacity with a pound of powder and one hundred lead bullets evenly distributed around it inside the casing, this is a very effective weapon, but difficult to sling far enough to be safe from the fragments. Fragmentation damage is pi+ instead of cut. Often used with a magical fuze (+$250).

This would hardly be an issue for defensive engagement, where you can safely sling such monsters from behind the safety of rather thick walls. For offense, if may be worthwhile to assign the specialists given such weapons a dedicated pavisier, probably using a special two-handed pavise that is angled upward to increase effective DR against the fragments. Sling the bomb, then duck behind the portable cover. The big issue here is going to be one of friendly fire (as your less-elite troops in the area aren't going to have a dedicated pavisier to hide behind).

Originally Posted by Icelander

Which... now that I think about it, sounds incredibly useful as a contact fuze.

Sure, a pint might be expensive at $100, but how much do you need to ignite smokepowder? A tiny vial that of alchemist's fire that breaks when the shell deforms and boom, your shell has a TL6 trigger, at least.

How small could the best glassblowers of the pre-Industrial world make glass vials?

I would have suggested this earlier, but your previous comparison of alchemist's fire to Greek fire / naptha made me think you weren't going the "ignites when opened" route with your alchemist fire. An issue with using alchemist's fire is that you pretty much have to have the outer shell made of metal, as otherwise cracking the vial is going to require cracking the shell, at which point you no longer have a proper explosion. If you want to be able to use an alchemist fire contact fuse with glass/ceramic bombs, some clever mechanism of a pin being pushed into the alchemist fire vial upon impact may be necessary. You'd need to design things so that aerodynamics favor the head of the pin being struck upon impact, however.

As for the size of the glass vials, I'd imagine experts could make truly tiny glass vials. If needed, a 1 mL glass vial would likely be possible, with very thin walls to facilitate breakage.


The biggest issue with using alchemist fire for fusing is that the weapon is always "armed." Older grenades could be dangerous, but you typically need to actually light them before they were ready to go - accidentally dropping an alchemist fire fused bomb is going to most likely result in an explosion. For safety it may be possible to have some sort of "arming" step involved (for metal-cased bombs, a removable-but-resealable cork might work, wherein you pop it open, toss in the vial, close it and seal it up; for bombs using the pin mechanism, maybe the pins could be removable?), but this may result in an increase in mass...

[Ulzgoroth]

If you're just providing pre-formed shrapnel, cast iron might be cheaper than bronze. Unlike making wire, making shrapnel should be easy to do with just iron-casting.

Unless your situation is that cast bronze is actually less costly than cast iron.

[Icelander]

Originally Posted by Ulzgoroth

If you're just providing pre-formed shrapnel, cast iron might be cheaper than bronze. Unlike making wire, making shrapnel should be easy to do with just iron-casting.

Unless your situation is that cast bronze is actually less costly than cast iron.

Ah, well, cast-iron is available, but has to be imported and stuff made in the the foundries that can make it is in very high demand.

On the other hand, there is a local abundance of bronze, a lot of it not in use.

The price, for the PCs, is more or less equivalent.* Since they need a lot of weapons in as little time as possible, they'll buy bronze, ceramic, glass and cast iron all.

*They are overpaying for the bronze, but are willing to do so in order to stimulate the local economy and encourage the almost vanished middle class (likely to have held on to some bronze).

[Icelander]

Originally Posted by Varyon

This would hardly be an issue for defensive engagement, where you can safely sling such monsters from behind the safety of rather thick walls. For offense, if may be worthwhile to assign the specialists given such weapons a dedicated pavisier, probably using a special two-handed pavise that is angled upward to increase effective DR against the fragments. Sling the bomb, then duck behind the portable cover. The big issue here is going to be one of friendly fire (as your less-elite troops in the area aren't going to have a dedicated pavisier to hide behind).

It's more dense than a rock and a 3-lb rock can be slung out to 80m by a man with some skill with a sling and decent muscle mass. A more typical ST 10 slinger ought to manage at least 55m, I should think, at least if he's using a two-handed staff sling and has been using sling since childhood. In any event, anything over 30 yards is probably more-or-less safe, if you're on a battlefield (in which case nothing is really safe, but a risk of injury or death that's way below 1%may be worth ignoring if there are other, more serious risks to worry about).

All the same, it's a weapon to treat with care and respect on the battlefield. Only issue it to sensible and level-headed specialists.

Originally Posted by Varyon

I would have suggested this earlier, but your previous comparison of alchemist's fire to Greek fire / naptha made me think you weren't going the "ignites when opened" route with your alchemist fire.

There is Thayan Fire, which is re-named Greek Fire from LT at $10 per pint, and there is Alchemist's Fire, from DF1, at $100 per pint. The latter self-ignites.

Originally Posted by Varyon

An issue with using alchemist's fire is that you pretty much have to have the outer shell made of metal, as otherwise cracking the vial is going to require cracking the shell, at which point you no longer have a proper explosion. If you want to be able to use an alchemist fire contact fuse with glass/ceramic bombs, some clever mechanism of a pin being pushed into the alchemist fire vial upon impact may be necessary. You'd need to design things so that aerodynamics favor the head of the pin being struck upon impact, however.

Impact will involve going from 30m/s up to 90m/s down to 0m/s in a very short period. That's a far greater shock than the acceleration of launch, which happens over a comparatively long time, relatively speaking.

I'm sure it's possible to design a mechanism which crushes a tiny glass vial inside it upon very rapid deacceleration. It might, however, have to be fairly expensive so as not to expose the troops to unreasonable risk of catastropic failure.

I'm thinking about a price range of $25 to $200 or so per fuze, with the sweet spot being around $50-$100. If they come out more expensive, the more reliable magical fuzes win out, whereas anything cheaper will likely be too dangerous to use and it's better to stick with a carefully made and measured quick-match with a cover of some sort.

I'm cool with there being two kinds, at least, a more complex pin-based one and a less complex one which works through deformation of metal casings. The former would be closer to the high end of pricing while the latter might approach the low end.

Originally Posted by Varyon

As for the size of the glass vials, I'd imagine experts could make truly tiny glass vials. If needed, a 1 mL glass vial would likely be possible, with very thin walls to facilitate breakage.

How much ought that cost?

Originally Posted by Varyon

The biggest issue with using alchemist fire for fusing is that the weapon is always "armed." Older grenades could be dangerous, but you typically need to actually light them before they were ready to go - accidentally dropping an alchemist fire fused bomb is going to most likely result in an explosion. For safety it may be possible to have some sort of "arming" step involved (for metal-cased bombs, a removable-but-resealable cork might work, wherein you pop it open, toss in the vial, close it and seal it up; for bombs using the pin mechanism, maybe the pins could be removable?), but this may result in an increase in mass...

I imagined that they'd insert an elongated tiny glass vial into a slot for a fuze just before engagements.

I imagine that the slot for the vial could be designed so that upon suddenly going from 30m/s to 0 in a sharp impact, the vial breaks, releasing the Alchemist's Fire to catch fire and leak into the shell. For any kind of projectile likely to deform, even slightly, this is an all but certain result of impact.

Others may require a more clever design, incorporating, as you say, some kind of pin.

[Varyon]

Originally Posted by Icelander

How much ought that cost?

No clue, honestly, although I doubt it would be much more than the vials used to hold potions in DF, so you might be able to use that as a baseline.
Using the right sort of glass (we did this in a chemistry lab to make some very thin capillary tubes once), a glassmaker could first construct a long, moderately thick-walled tube. Afterwards, heat up the glass enough to be near melting and simply stretch it out to get a very long, very thin, thin-walled tube. After this he need simply break off sections and seal one end (via partial melting) and you have your vials. If alchemist fire is something that has a short wait after it's made before it becomes sensitive to air, it might be possible to make fully-sealed vials of alchemist's fire using such a method (melt-sealing both ends after it's already full).

$75 for the "crush" fuse and $100 for the "pin" fuse might be appropriate, although I'm honestly just kind of throwing numbers out. Note the crush fuse would have a better reliability than the pin, as it need merely impact strongly enough (without cracking the shell), while the pin fuse has to impact at a certain point on the projectile.

[Icelander]

Originally Posted by Varyon

$75 for the "crush" fuse and $100 for the "pin" fuse might be appropriate, although I'm honestly just kind of throwing numbers out. Note the crush fuse would have a better reliability than the pin, as it need merely impact strongly enough (without cracking the shell), while the pin fuse has to impact at a certain point on the projectile.

A correctly thrown biconical sling projectile will impact with either end, as long as it hits. Imagine an American football.

As long as you are willing to have some mechanism in both sides, you ought to be good.

If the vial is only $5 and we need only a few drops of Alchemist's Fire, I can't see any reason for the basic fuse to cost more than $10.

Add maybe $10 for safety and ease-of-use considerations (good hand grips, a way to screw it in, etc.), as well as another $10 for some basic features that allow it to slot into the projectiles. I think that $25 sounds about right for the fuze.

If the projectile is going to deform, that's all you need.

A pin mechanism justifies additional cost above that, of course. Judging from the rules for locks, maybe another $25 would be fair. And you'd need one fuze for each end of the projectile.

So you'd be at $25-$100, depending.

[Varyon]

Originally Posted by Icelander

A correctly thrown biconical sling projectile will impact with either end, as long as it hits. Imagine an American football.

As long as you are willing to have some mechanism in both sides, you ought to be good.

Agreed. However, there will be cases where the projectile is either not correctly thrown (a slinger in a rush, or perhaps one that is himself struck while slinging) or where it gets sent into a tumble (turbulence from a nearby explosion, glancing off a target - or the target's weapon/shield for a just-barely-failed defense - but then hitting something else nearby; heck, with massed slingers it may occur that you have the stones themselves glancing off each other mid-flight). These probably wouldn't have an effect on the crush fuse, but likely would on the needle mechanism.

Originally Posted by Icelander

If the vial is only $5 and we need only a few drops of Alchemist's Fire, I can't see any reason for the basic fuse to cost more than $10.

Add maybe $10 for safety and ease-of-use considerations (good hand grips, a way to screw it in, etc.), as well as another $10 for some basic features that allow it to slot into the projectiles. I think that $25 sounds about right for the fuze.

If the projectile is going to deform, that's all you need.

A pin mechanism justifies additional cost above that, of course. Judging from the rules for locks, maybe another $25 would be fair. And you'd need one fuze for each end of the projectile.

So you'd be at $25-$100, depending.

That looks fair enough.

[johndallman]

Is there a role for light trebuchets on these battlefields? If so, it's worth building heavier projectiles for them, and standardising the dimensions and weights tightly enough that one can take ranging shots with rocks.

[Icelander]

Originally Posted by johndallman

Is there a role for light trebuchets on these battlefields? If so, it's worth building heavier projectiles for them, and standardising the dimensions and weights tightly enough that one can take ranging shots with rocks.

The 1-3 lbs. shot will be delivered with a heavy staff sling, which is not so very unlikely a light trebuchet, of course.

You were thinking about something man-portable in the size range above that?

That role is more-or-less handled with ballistae, but those aren't very man-portable. Even so, they are lighter than anything using indirect fire in Low-Tech.

If you have some real-world contraptions with better performance than result from merely scaling down the artillery stats* in Low-Tech, I'd be very interested. By all means, suggest devices in the TL3+1 Mechanical Artillery thread.

Any way of delivering a 5-lb or heavier projectile to 60 yds range or longer is interesting, if it can be done with something one or two men can carry and mount on the battlefield. As long as it could be built with the technology base that the PCs have, it's potentially allowed, even if it was never invented in real history.

*Which I don't always understand how are derived.