Got a Real-World Weapon, Armour or Tactics Question? Mk. XXX

[halfeye]

Blantantly copied from the previous thread:

Real World Weapon, Armour and Tactics Thread XXIX

This thread is a resource for getting information about real life weapons, armour and tactics. The concept has always been that the information is for RPG players and DMs so they can use it to make their games better, thus it's here rather than in Friendly Banter.

A few rules for this thread:

• This thread is for asking questions about how weapons, armour and tactics really work. As such, it's not going to include game rule statistics. If you have such a question, especially if it stems from an answer or question in this thread, feel free to start a new thread and include a link back to here. If you do ask a rule question here, you'll be asked to move it elsewhere, and then we'll be happy to help out with it.
• Any weapon or time period is open for questions. Medieval and ancient warfare questions seem to predominate, but since there are many games set in other periods as well, feel free to ask about any weapon. This includes futuristic ones - but be aware that these will be likely assessed according to their real life feasibility. Thus, phasers, for example, will be talked about in real-world science and physics terms rather than the Star Trek canon. If you want to discuss a fictional weapon from a particular source according to the canonical explanation, please start a new thread for it.
• Please try to cite your claims if possible. If you know of a citation for a particular piece of information, please include it. However, everyone should be aware that sometimes even the experts don't agree, so it's quite possible to have two conflicting answers to the same question. This isn't a problem; the asker of the question can examine the information and decide which side to go with. The purpose of the thread is to provide as much information as possible. Debates are fine, but be sure to keep it a friendly debate (even if the experts can't!).
• No modern real-world political discussion. As the great Carl von Clausevitz once said, "War is merely the continuation of policy by other means," so politics and war are heavily intertwined. However, politics are a big hot-button issue and one banned on these boards, so avoid political analysis if at all possible (this thread is primarily about military hardware and tactics). There's more leeway on this for anything prior to about 1800, but be very careful with all of it, and anything past 1900 is surely not open for analysis (These are arbitrary dates but any dates would be, and these are felt to be reasonable).
• No graphic descriptions. War is violent, dirty, and horrific, and anyone discussing it should be keenly aware of that. However, on this board graphic descriptions of violence (or sexuality) are not allowed, so please avoid them.
• A few additional comments following the premature demise of thread XXVI: Words from Roland St. Jude.

With that done, have at and enjoy yourselves!

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Thread XXIX

I hope I didn't get too much wrong.

[halfeye]

The firing of a bow cannot be modeled in the same way as the firing of a gun. There are factors that are important to a bow’s ability to impart energy to an arrow that are not present with a gun. If your approximation does not account for that, it will give the wrong answer.

Additionally, I feel your claim that the firing of a gun can be modeled as an elastic collision needs support. By definition, an elastic collision preserves kinetic energy. When firing a gun, everything is stationary in the initial state, hence no kinetic energy. At the time the bullet exits the muzzle, it has nonzero velocity. Since the bullet also has nonzero mass, this means the system has nonzero kinetic energy. Going from zero kinetic energy to nonzero kinetic energy clearly is does not represent kinetic energy being conserved.

Bear in mind, kinetic energy is necessarily a non-negative value. It’s equal to mass times the square of velocity. Mass can’t be negative, and while velocity can be negative, squaring a negative number still results in a positive number. There’s just no way to get a negative kinetic energy, so there’s no cancelling out the kinetic energy of the bullet-in-motion.

You can use conservation of momentum if you want. That still applies. But momentum being conserved isn’t enough to call an interaction an elastic collision.

Additionally, the litmus test of the validity of any approximation is to compare the predicted results to actual experimental data. I can refer you to tests showing heavier arrows possessing greater kinetic energy even at point-blank range.

The reasons heavy arrows tend to have better energy retention is due to how
constant the rigidity the shafts/dynamic spine have when combined with heavy draw weights.

There is even a famous paradox covering it. It's very easy to "over power" light quarrels with powerful bows and sap energy, accuracy, and even structural integrity.

Well, no, almost nobody measures arrows velocity at long range, it's pretty challenging, to say at least. 99% measurements are from few meters at least, and mentioned Karpowicz test where made with window of chronograph about 1 yard away from the bow.... We're talking about very initial velocity.

KE energy being square of velocity obvisouly works both way, if you want to speed something up two times, you need to put in 4 times more energy. Increasing speed isn't easy.

Many very good composite bows are close to 95% efficient in ideal conditions (heavy arrows, perfect, instant release), so even if there were somehow more efficient with light arrows as with heavy ones, there wouldn't be any energy more to gain.

The fact that bows of all kind are visibly more efficient with heavier arrows really isn't disuptable.

Here are menioned Karpowicz tests:

https://www.atarn.org/islamic/akarpo..._bow_tests.htm

Here's a ballistic for some modern crossbows by deer and deer hunting.



Heavier arrows yield more KE.




Generally, the opposite seems to be true, if anything.

For given caliber, amount of propeller, and barrel length, and shape, heavier bullet will tend to have bit more energy.

Note that having everything but bullet weight being identical is nigh-impossible for a large majority of firearms even if it were desirable, because anything except a single-loader has pretty major constraints on overall length (it will fit in the chamber just fine, but any kind of feeding system tends to have trouble if the bullet is much longer than expected). This means that usually to get a heavier bullet, you usually have to change the shape - a standard 115 grain FMG 9mm round comes to a smooth roundness, a 147 grain FMJ round has a massive flat tip, for example.

That said, the two rounds generally have pretty close to the same energy if the propellant and the barrel length is the same. The heavier bullet retains more velocity at range, though being slower it has just a bit worse ballistics and flight time. The heavier round having the same energy is often the reason to make it, in scenarios where a slower speed is valuable in and of itself (the most common such scenario being suppressors, where you want to drop the bullet below the speed of sound to eliminate the supersonic crack).

I admit I was assuming that light arrows were structurally capable of being fired with the bow's full power, if that's not the case then all my working was wrong, an arrow made of wet spaghetti is going nowhere.

[Vinyadan]

Wet spaghetti are pretty heavy though, it's uncooked spaghetti that would be too light.

[Maat Mons]

I'm saddened that no one else liked my suggestion of dedicating this new thread to classic cinema.

[halfeye]

I'm saddened that no one else liked my suggestion of dedicating this new thread to classic cinema.

I waited what felt like a week before restarting the thread, because nobody else did and I had something to say. I didn't remember that idea, as I usually don't remember things.

[Maat Mons]

I'm glad someone started the new thread. It had been quite a while. I briefly considered starting it myself, and putting the reference in. But I didn't want to force it if I was the only one amused by the notion. Nevertheless, I feel no qualms complaining about things it was fully in my power to avoid.

[Pauly]

I admit I was assuming that light arrows were structurally capable of being fired with the bow's full power, if that's not the case then all my working was wrong, an arrow made of wet spaghetti is going nowhere.

Not an archer or a physicist so I’m not sure if this helps the debate or not.
Historically speaking light arrows are often referred to as ‘target’ arrows, ‘flight’ (i.e. long range) arrows or ‘bird’ arrows. Heavier arrows are called ‘hunting’ or war’ depending more on the intended purpose than weight.

Exact nomenclature depends on time, location and culture.

[Spiryt]

I admit I was assuming that light arrows were structurally capable of being fired with the bow's full power, if that's not the case then all my working was wrong, an arrow made of wet spaghetti is going nowhere.

The reasons heavy arrows tend to have better energy retention is due to how
constant the rigidity the shafts/dynamic spine have when combined with heavy draw weights.

There is even a famous paradox covering it. It's very easy to "over power" light quarrels with powerful bows and sap energy, accuracy, and even structural integrity.

If it was all about arrow structure being able to "take" bow limbs energy, then two bows of similar energy storage wouldn't have such drastically different performances with light arrows.

100 pound 30 inches Korean flight bow will likely be few to something-teen % faster with 1300 grain arrow than well made 100 30 inch yew selfbow, but completely outclass it with 200 grain arrow.


It's about angles, internal friction in limbs, limbs weight, hysteresis and couple of other things I'm not sure about, but in any case heavier arrows will always have at least few % more KE.

[halfeye]

If it was all about arrow structure being able to "take" bow limbs energy, then two bow of similar energy storage wouldn't have such drastically different performances with light arrows.

100 pound 30 inches Korean flight bow will likely be few to something-teen % faster with 1300 grain arrow than well made 100 30 inch yew selfbow, but completely outclass it with 200 grain arrow.


It's about angles, internal friction in limbs, limbs weight, hysteresis and couple of other things I'm not sure about, but in any case heavier arrows will always have at least few % more KE.

In that case, the light arrows aren't holding up to the stress. The difference between the bows might be the length of the arms, longer would be kinder to light arrows.

[Spiryt]

In that case, the light arrows aren't holding up to the stress. The difference between the bows might be the length of the arms, longer would be kinder to light arrows.

Traditional flight bows tend to have shorter arms....

Korean flight bows in particular could apparently be as short as 45 inches tip to tip.

[stoutstien]

In that case, the light arrows aren't holding up to the stress. The difference between the bows might be the length of the arms, longer would be kinder to light arrows.

longer arms usually means a longer shaft which has a sharp diminishing return when you are trying to apply force to one end and a noticable amount of the weight is on the other unless you also make it more rigid which means more weight. They just can't absorb the energy like a heavier quarrel will. If you can't translate all that kinetic energy into something usable like penetration, momentum, and consistently it's wasted.
The only real advantage the lighter arrows have are needing less draw weights and a flat(er) trajectory/shorter flight time. Great for field shooting or other types of target based sports but for anything large enough to considered dangerous or is fighting back those are low priorities.

When you are looking at the lethality of arrows you want enough speed to get it there and puncture 'past' a vital area and the rest of the bows energy is preferably stored in a transferable form stored in the arrow.

Regarding bows meant for battle you also have a weird effect with heavier arrows needing weaker draw strengths for comparable results with lighter ones. (Well weird as unintuitive but that's just physics). This means for making multiple shots over a short period of time the light draw weight/heavy arrows combo wins on the practical side as well.

[Maat Mons]

Watching this video (and then this one) has me wondering, how well would a sword stand up to being used as a machete? Would that thinner, lighter blade be a major hindrance to chopping brush? Would your sword edge get too dull from trailblazing to serve adequately as a sword?

Also, where would you choose to wear a sword if you were trudging through dense vegetation? Traditionally, machetes are worn on the back, which isn't good for drawing quickly, and swords are worn at the hip, which would they'd be getting tangled in the underbrush.

[stoutstien]

Watching this video (and then this one) has me wondering, how well would a sword stand up to being used as a machete? Would that thinner, lighter blade be a major hindrance to chopping brush? Would your sword edge get too dull from trailblazing to serve adequately as a sword?

Also, where would you choose to wear a sword if you were trudging through dense vegetation? Traditionally, machetes are worn on the back, which isn't good for drawing quickly, and swords are worn at the hip, which would they'd be getting tangled in the underbrush.

Swords are a broad category. Historically they even had some that were made for chopping/sawing through vegetation like the pioneer sword and a machete is just a falchion with a different cutting edge.

For carrying location I'd go for over shoulder slung if I'm planning to be using it off and on all day but it would need to have flexibility on how it can be carried to be changed depending on terrain and need.

[Catullus64]

Got some questions about slings. First, what kinds of wounds do they inflict? Do the stones inflict blunt trauma, or are they likely to penetrate the body?

What are the characteristics of slings in comparison with other muscle-powered missile weapons, particularly bows? Do they enjoy advantages in accuracy, effective range, or ease of training?

How well are slings likely to perform against different kinds of armor?

[Gnoman]

The great virtue of slings is that a lot of pastoral cultures had lots of people with the skill to use them. They require no material except leather, and can use stones for ammunition (though cast-lead bullets were popular for ammunition), so any society that tended and killed animals could produce them cheaply. This more than offset the fact that they are a fairly difficult weapon to use - shepherds and the like often had plenty of time to practice, and regular need of a cheap and reliable ranged weapon to drive off animals that might prey upon their flock.

In terms of damage, the term "bullet" used for the purpose-made ammo is instructive. While significantly slower than a bullet from a gun, sling bullets were quite heavy, giving them quite impressive energies. I've seen some modern tests that suggested energies similar to modern pistol rounds, which is significant. Being rather larger and slower would affect the wounds - they aren't going to make the same kind of neat little hole, obviously - but that's still a very heavy hit. Many recovered sling bullets are heavily deformed from impact, and there are written sources suggesting that this was so common that the ancients believed that the rounds were actually melting in flight (this is impossible - modern experiments with firearms show melting only at extreme velocities far beyond the reach of any muscle-powered weapon).

In accuracy and range, there's sources to suggest that slings were comparable to bows as well. The real killer is that if you weren't recruiting men who'd used slings from boyhood, it took far longer to train a slinger than it did an archer.

[Maat Mons]

Actually, you can make a sling without leather. Leather was very popular for the "cradle" or "pouch," but you cold also form it by braiding the same maerial used for the chord (usually flax, hemp, or wool).

[Gnoman]

Good point. The key is that slings were fundamentally cheap - you don't need wood or horn to make a bowstave, you don't need metal for arrowpoints, or feathers for fletching. Just a few scraps of material and some rocks.

[stoutstien]

Even with natural stones and clay shot a sling can apply enough energy to kill someone in late period plate by completing caving it in. With lead shot I wouldn't be surprised if you could get a clean piercing blow at short range vs plate/mail. Plenty of records of the Spanish dealing with deaths at long range (up to 400 meters)from Aztec slings let alone point blank blows and the Romans has special tools for removing sling shot from the wounded.

The time it takes to master is was really the reason it fell out of favor as a weapon of war.

[Gnoman]

Plenty of records of the Spanish dealing with deaths at long range (up to 400 meters)from Aztec slings let alone point blank blows and the Romans has special tools for removing sling shot from the wounded.

Don't extrapolate too much from this. The Spanish abandoned a lot of their armor because the environment they were in was so hot and humid. This is well documented. There's also a lot of second-order reports from people who weren't there making assumptions on what happened that have been heavily conflated with the eyewitness reports. Not to mention, of course, that the vast bulk of the forces used by Spain against the Aztecs were locals - the relatively small number of Spaniards allied with many of the Aztec's long-term enemies, who never had late-era steel armor in the first place.

That the Spanish took casualties from slings is almost certainly true. That doesn't mean that the slings punched through armor meant to stop musket and pistol fire. There's a good chance that the casualties in question were unarmored entirely.

If slings could punch through a 16th century breastplate at all, no difficulty in learning the weapon would have stopped ancient empires from imposing sling training by force. Because if a Spanish breastplate won't stop it, absolutely nothing will. Guns probably would never have been adopted at all.

[Catullus64]

Don't extrapolate too much from this. The Spanish abandoned a lot of their armor because the environment they were in was so hot and humid. This is well documented. There's also a lot of second-order reports from people who weren't there making assumptions on what happened that have been heavily conflated with the eyewitness reports. Not to mention, of course, that the vast bulk of the forces used by Spain against the Aztecs were locals - the relatively small number of Spaniards allied with many of the Aztec's long-term enemies, who never had late-era steel armor in the first place.

That the Spanish took casualties from slings is almost certainly true. That doesn't mean that the slings punched through armor meant to stop musket and pistol fire. There's a good chance that the casualties in question were unarmored entirely.

If slings could punch through a 16th century breastplate at all, no difficulty in learning the weapon would have stopped ancient empires from imposing sling training by force. Because if a Spanish breastplate won't stop it, absolutely nothing will. Guns probably would never have been adopted at all.

I was also inclined to be skeptical of slings penetrating plate armor, but I do wonder if they could impact hard enough to injure someone in plate armor via concussive force, particularly if they struck a helmeted head. Thoughts?

[VonKaiserstein]

I don't have any firsthand knowledge- but my googlefu turned up this very detailed paper by Erik Skov. He presents quite a bit of data and evidence to support his conclusions.

https://digitalcommons.unl.edu/cgi/v...t=anthrotheses

[stoutstien]

Don't extrapolate too much from this. The Spanish abandoned a lot of their armor because the environment they were in was so hot and humid. This is well documented. There's also a lot of second-order reports from people who weren't there making assumptions on what happened that have been heavily conflated with the eyewitness reports. Not to mention, of course, that the vast bulk of the forces used by Spain against the Aztecs were locals - the relatively small number of Spaniards allied with many of the Aztec's long-term enemies, who never had late-era steel armor in the first place.

That the Spanish took casualties from slings is almost certainly true. That doesn't mean that the slings punched through armor meant to stop musket and pistol fire. There's a good chance that the casualties in question were unarmored entirely.

If slings could punch through a 16th century breastplate at all, no difficulty in learning the weapon would have stopped ancient empires from imposing sling training by force. Because if a Spanish breastplate won't stop it, absolutely nothing will. Guns probably would never have been adopted at all.

I said I wouldn't be surprised if one could do so not that it did so on any regular basis.

The fact a sling took a life time to master and has issues with precision compared to the ease of use and relative consistency of firearms shouldn't be overlooked but if you are talking about raw potential damage even someone like me (who is only an amateur with slings) can produce similar energy levels as a major league baseball bat swing. The fact it transfers energy without needing penetration is why is was used but that doesn't mean it was incapable of doing so.

I would say it would be extremely rare due to the lack of ability to have control of the angle of approach, pin point shot placement, and the relatively soft material used for shot but the number of times I've had armor failed "proofing" would lead to the conclusion that its possible.

[dspeyer]

A question about guns: What's the relationship between barrel width and weight?

I'm trying to write a system that allows for flexible gun customization. When I look at example real-world guns, it seems like barrel widths from 5mm (.22 cal) to 20mm (12 gauge) weight about the same, but as soon as you go to 25mm everything gets much, much heavier.

Is there some extreme nonlinearity? If so, why are 150mm guns mobile with small teams of oxen?

Is it that anyone who bothers to make a 25mm gun adds other heavy features? If so, what?

Thanks from a gun newb

[stoutstien]

A question about guns: What's the relationship between barrel width and weight?

I'm trying to write a system that allows for flexible gun customization. When I look at example real-world guns, it seems like barrel widths from 5mm (.22 cal) to 20mm (12 gauge) weight about the same, but as soon as you go to 25mm everything gets much, much heavier.

Is there some extreme nonlinearity? If so, why are 150mm guns mobile with small teams of oxen?

Is it that anyone who bothers to make a 25mm gun adds other heavy features? If so, what?

Thanks from a gun newb

Max chamber pressure and heat displacement is more important than caliber when you are looking at wall thickness. That's why shotguns can have thinner barrels. Even the punt guns which could have a 10+ ft barrel only clocked in at around 100 lbs even they they threw over a pound of lead in a shell because they had low pressures to deal with.

Lobbing gobs of material over great distances from a dead stop means you need a lot of pressure. Cast iron cannons were prone to failure due to both the heat and pressure making or finding weak points. modern artillery is meant for frequent use so it's built to eat it in strides. You don't get that without mass. Heat is also an issue if you don't sink it away. See cooking off and thin/light walled larger caliber option such as leather cannons.

[Gnoman]

I said I wouldn't be surprised if one could do so not that it did so on any regular basis.

The fact a sling took a life time to master and has issues with precision compared to the ease of use and relative consistency of firearms shouldn't be overlooked but if you are talking about raw potential damage even someone like me (who is only an amateur with slings) can produce similar energy levels as a major league baseball bat swing. The fact it transfers energy without needing penetration is why is was used but that doesn't mean it was incapable of doing so.

I would say it would be extremely rare due to the lack of ability to have control of the angle of approach, pin point shot placement, and the relatively soft material used for shot but the number of times I've had armor failed "proofing" would lead to the conclusion that its possible.

A sling bullet penetrating armor meant to resist muskets is not "extremely rare". It's "physically impossible". Can't happen.

A question about guns: What's the relationship between barrel width and weight?

I'm trying to write a system that allows for flexible gun customization. When I look at example real-world guns, it seems like barrel widths from 5mm (.22 cal) to 20mm (12 gauge) weight about the same, but as soon as you go to 25mm everything gets much, much heavier.

Is there some extreme nonlinearity? If so, why are 150mm guns mobile with small teams of oxen?

Is it that anyone who bothers to make a 25mm gun adds other heavy features? If so, what?

Thanks from a gun newb

Answering this question requires an understanding of how guns work. You're almost certainly aware of this, but some of the effects and consequences may not be immediately obvious, and starting from the basics is a good way to make sure that all the terms are defined.

A gun is fired by detonating a quantity of propellant behind a projectile. This propellant burns very rapidly (actually explodes, in the case of black powder), generating immense amounts of pressure in the confined space. The area in which this happens is called the chamber, and the amount of force present in this area is called the chamber pressure. This pressure pushes in all directions, forcing the unsecured projectile down the barrel. Pressure drops as the available volume expands, but the propellant is still burning and generating pressure, meaning that it doesn't drop to zero. This means that not only does the chamber have to withstand pressure, the barrel does as well. Additionally, the burning powder is dumping serious amounts of heat energy into the environment. In a cartridge-based firearm, a huge portion of this heat is contained within and removed with the metallic cartridge case (even a .22 casing that has just been fired is hot enough to cause burns - I have a small scar on the inside of my right elbow from just such an occurrence), but the rest (minus a portion that exits along with the projectile) gets dumped into the gun itself. Most of this (particularly since the portion dumped into the chamber is mostly absorbed by the cartridge as mentioned) is absorbed into the barrel. The barrel continues to confine the expanding burning propellant, keeping pressure up (and continuing to accelerate the projectile) until one of two things happen. Either the projectile will exit the gun, at which time the pressure will drop to zero and there will be no further acceleration, or else the propellant will be fully exhausted and the projectile will begin to decelerate due to friction from contacting the barrel.

Thus, the barrel of a firearm has two universal functions.

The first and most obvious is containing the pressure wave from the propellant. This requires it to be strong enough not to burst, and be of appropriate length for the standard propellant load - too short and you waste much of the powder, too long and you lose power from friction.
The second, less obvious function is that it serves as a heat sink. Firing a gun generates a lot of heat, and that heat has to go somewhere. If a barrel isn't built heavily enough, that heat can make Bad Things happen - from a shift in the point of aim to outright catastrophic failure.

Additionally, for hand-held firearms (pistols, rifles, and shotguns) and crew-served weapons fired over open sights, the barrel carries a third function - it mounts the iron sights. In general, a gun is more accurate the longer the distance between the front and rear sights - the sight radius - is. This is because the longer the sight radius is, the less margin of error, and thus chance of inaccuracy, you have in aligning the sights.

On the other side of the spectrum, you have a number of other design factors to consider.

1. Cost - a longer and heavier barrel costs more, because it has more material. Meanwhile, a barrel that's lighter but stronger due to advanced materials also costs more, because exotic materials cost more.
2. Weight. Depending on design role, how much a gun barrel weighs (and consequently how heavy the gun itself is) can be very important. A rifle that spends its entire life sleeping in a safe except for when it is being driven to a competition range, fired from a rest, and then driven back to the safe can be as heavy as you want it to be. A rifle of similar design that some private is going to be carrying through the desert for 16 hours a day? You don't want that to weigh an ounce more than it absolutely has to. This is true of bigger guns as well - the main gun of a destroyer is far heavier than the main gun of a battle tank, even though the caliber is usually very similar, because transporting a tank is a lot more involved than a boat just sailing around.
3. Bulk. This is a big one. Any gun that gets moved around a lot has to take this into account, because it factors into shipping (tanks and self-propelled artillery are extremely inconvenient to transport because of the gun even if you lock the turret into "travel position"), mobility in service (a full-sized rifle is not easy to move about in close quarters) and simple carriage (most concealed-carry pistols, for example, have very short barrels because a longer one is very awkward to shove into your pants).


This means that there's an enormous number of factors that go into the construction of a gun barrel. Two guns of the same basic model could have very different barrels depending on their intended use case - the barrel on my 10/22 is almost two pounds lighter than the one on my neighbor's gun, because mine's a general purpose model and his is configured as a dedicated target gun. This means you aren't going to GET a hard and fast rule, because there's no such thing.

[Pauly]

Re slings and the Spanish.
The Incas used slings heavily, the Aztecs more typically used darts launched from an atl-atl.
The Incas had access to high iron content stones (80%+ iron iirc), most famously used as hannerstones for their quarrying, and are documented as using these stones as shot in their war slings.

In Anabasis Xenophon describes Rhodian slingers with lead shot outranging Persian slingers and archers.


Re barrel thickness.
Some other factors to consider.
1) Metallurgy. Higher quality smelting and alloys allow barrels to be made thinner for the same strength.
2) Sustained fire. Only really a concern with automatic weapons, but thicker barrels are more resistant to deforming due to heat stress. It can be a concern with semi-autos with light barrels that are fired more rapidly and for longer than intended.

Edit to add:
Re gun weights.
Being engineered to be person fired also means compromises are made to keep the weight within an acceptable range for carrying by 1 person.
Once you get beyond shoulder fired weaponry you start getting into another realm of design choices.
Carriages.
The tl;dr version is that the more functionality you want to have in your carriage the heavier it will be. For example for MGs a tripod mount is more stable, more accurate and allows the firer to do more things than a bipod mount. However a tripod is much heavier, much harder to move, and much harder to hide than a bipod.
Similarly a Flak 37 and a PAK 43 have near enough to the same gun barrel and breech yet the FLAK 37 is a much bigger mount because of the AA functionality required.
Recoil. Carriage weight also depends on how much recoil is applied. Generally speaking true guns or cannons will have more substantial recoil than howitzers of the sane caliber. Carriage design, hydro-pneumatic recoil systems, semi-automatic systems that use energy from the recoil to reset the breech also can affect the amount of recoil the carriage needs to manage and thus overall carriage weight.
Recoilless rifles can be made with very light carriages because they don’t have to deal with recoil.
Transport/visibility. How the gun is intended to be moved will affect the design of the carriage. Generally speaking a weapon designed towed behind trucks on a road will require a more robust carriage than one designed to be a horse drawn or man pushed. Certain weapons are designed to be used in direct fire roles, the best example being ATGs. Weapons primarily designed for direct fire will have lighter carriages because of the need to reduce their visibility, and also the lack of need for high elevation firing.

[Sapphire Guard]

What would be the best way to cook food using fire while trying to hide your location if someone is looking for it? Would daytime or nighttime be better? What's easiest to spot from further away.

This is one person on foot, so there is a limit to how much they can carry and how far they can travel. She's living alone, hunting for food, but can't risk food poisoning because she's alone in the wilderness, trying to bring as little notice to her home as possible.

[tyckspoon]

What would be the best way to cook food using fire while trying to hide your location if someone is looking for it? Would daytime or nighttime be better? What's easiest to spot from further away.

This is one person on foot, so there is a limit to how much they can carry and how far they can travel. She's living alone, hunting for food, but can't risk food poisoning because she's alone in the wilderness, trying to bring as little notice to her home as possible.

So your main concerns are, of course, light and smoke. Light is much more visible at night, smoke is more visible during the day (caveat: smoke stands out less against a night sky than day, but a sufficiently think plume will still be quite visible against star or moonlight.) Your best method/time to try to cook will depend on which of those factors you are better able to control. Smoke is reduced primarily by having better quality fuel - the more readily and completely your fuel burns, the less it will smoke. That usually takes time and preparation - making charcoal, storing and drying out firewood, rendering flammable oils, whatever - which your character probably doesn't have the luxury of doing, nor the individual carrying capacity to try to lug around dozens of pounds worth of ready to use fuel.. so, assuming they are needing to rely largely on fallen/found wood (because cutting down live wood both produces very poor quality fuel and leaves really obvious signs that somebody is harvesting wood) then they can't do much about the smoke. That suggests they're probably doing what they can to cook at night, and will be doing their best to manage the amount of light they produce and the directions from which that light can be easily seen.

So.. make only the amount of fire you absolutely strictly need (this also reduces the amount of smoke you make and the trackable traces of where you were - ashes, spots where you burnt away grass/left burn marks on stones, etc, so this is probably the number one thing in general.) Make your fire in a place where visibility is reduced. If possible, construct or hang barriers to reduce the number of directions your firelight can be easily seen from. Helps if you know which direction(s) your possible pursuers may be searching from. After your fire is done do your best to remove signs of having had a fire there, in case your pursuers find one of your old campsites but not you.

[PhoenixPhyre]

As for light, I'd assume doing some kind of buried pit (like is done in very windy areas) will be best. Slow, for sure. But easy to contain and dispose of in a way that leaves little trace.

[stoutstien]

If a fire for food is unavoidable (air curing/pasteurizing water isn't that hard if you are looking to minimize your foot print) then i would probably stick to the day time and used forced air feed fire methods to practically eliminate smoke and heat stuff quickly. Look up Dakota style pits.

Id quickly heat up some sort of sink like metal or stones and go from there.