Leopard 2A7I vs RX-78-2 Gundam

[Gunhead]

If you're that close to a 120mm cannon going off, the overpressure will turn you into paste.
My guess is the people making the anime just didn't know / forgot this. It's that or robit guns have magic to reduce the blast to extremely low levels or their rounds are very low power.
And by low power I do mean the vehicle equivalent of a nerfbat.

-Gunhead

[Stark]

I don't want to be rude or anything, but when people keep using the same example of something to ignore the other 30 years of data, it makes me lol.



Remember all those times Star Trek people tried to use individual examples to override the broader set of data and how well that worked? Space propellant? A misfire? No, lets decide that all 120mm shots ever are way slower than they look because we're idiots!

[Connor MacLeod]

If you're that close to a 120mm cannon going off, the overpressure will turn you into paste.
My guess is the people making the anime just didn't know / forgot this. It's that or robit guns have magic to reduce the blast to extremely low levels or their rounds are very low power.
And by low power I do mean the vehicle equivalent of a nerfbat.

-Gunhead

Or quite possibly, its not firing a projectile via chemical propellants. Or maybe not firing a conventional projectile at all. THere's absolutely no propellant blast from firing the weapon - and this is supposed to be a 120mm round firing off. Even if Shiro hadn't been pulverized by overpressure, he'd be cooked by the firing of the gun in all probability.

Add to the fact the shot is moving perfectly straight throught he atmosphere with no drop in gravity and you get the same problems you get with most sci fi zippy 'bolts'. But unlike something like Star Wars you can't really handwave miniature antigrav bullshit to excuse it in Gundam.

In any event its pretty silly to generalize from one example, since in the very same episode you have gunfire traveling at multiple km/s (and in at least one other episode in that same series, with the Magella tanks.)

However you try to explain it, there's more to it than just SLOW BULLETZ LOLZ

[Zinegata]

It bears to remember a couple of things:

The 120mm shell from the Zaku II is not necessarily analogous to the modern-day 120mm from an MBT gun. Given how fast the damn thing fires, it might not even be realistic to assume that it fires with the same kinetic punch as a modern M1 Abrams, or else the barrel is going to wear out very quickly.

There are indications that it's a low-velocity (albeit not ridiculously low velocity that a man can dodge it at point-blank range!) weapon meant primarily for space combat against battleships, as it is one of the Zaku II's original weapons. Maybe the shell was designed primarily to operate in space (with no atmopshere to hindre its performance) hence its funkiness and general ineffectiveness against well-armored targets in an atmosphere environment like the Gundam.

It's also worth noting that the EF and Zeon both generally switch to 90mm shells later in the war - such as those seen in Stark's compilation about 30 seconds in. The lighter shell may allow for higher velocities needed for MS vs MS combat.

[Formless]

Just going to throw this one out, but their shells could also incorporate rocket boosters downrange (like an upscaled gyroget) to keep the velocity high without eroding the barrel. That would explain the low muzzle velocity without diminishing the weapon's downrange impact. Could be practical for a skyscraper scale weapon. And it might add the pew pew tracer bullet look as a bonus.

[edit] oh, and it might be why you don't see giant spent shell cases hit the ground in most of those scenes Stark posted. They don't have them because they're rocket fired. Possibly. [/edit]

Just because it fires bullets doesn't mean they're not futuristic.

[Stark]

The simplest explanation that doesn't ignore the bulk of evidence seems to me that it was a misfire or partial detonation or other malfunction. The 120s are variously shown at all kinds of different performance, and its important to note that the machineguns usually have the muzzle flash scaled like a regular gun held by a person rather than an artillery piece, but Shiro was right there and I'm not sure ammo types explain the 'amazing feat'. :v Its just one example and a poor one to judge performance by.

[Zinegata]

Just going to throw this one out, but their shells could also incorporate rocket boosters downrange (like an upscaled gyroget) to keep the velocity high without eroding the barrel.

It's possible but a bit on the awkward side. I'm more inclined to think the 120mm rounds are primarily High-Explosive rounds, which to maximize explosive content has only thin shell casings and thus can be fired only at relatively low velocities - something similar to the Sheridan's 152mm gun.

From what I recall there were pretty big explosions when the Gundam was getting his by 120mm shells (that caused no damage) - which indicates a lot of explosive content but not great armor-piercing capability.

[Zinegata]

Side note on metallic shields absorbing energy weapon fire without obvious damage: this is actually very possible, if the material in question has extremely good thermal properties and isn't so good at blocking radiation that all the energy is dissipated into the top layer of material. You could get a situation where, say, roughly a cubic meter of armor material is heated to a dull red heat by the beam, with only the most superficial damage if any- and then that armor material steadily conducts its heat away to the rest of the surface of the shield, has it radiate/convect away into the air and so on, and when the smoke clears there is no evidence that the plate took a significant hit.

Meanwhile, shooting the same plate with 3-4 times the beam intensity could be enough to cause permanent scarring/cratering/melting.

Sorry, missed this. That's an interesting note.

Question though... How good are current titanium alloys in terms of thermal conduction that you mentioned above? I ask because Gundam Mobile Suits of all makes (even lightly armored ones) are supposed to be armored mainly using titanium alloys.

[Gunhead]

Or quite possibly, its not firing a projectile via chemical propellants. Or maybe not firing a conventional projectile at all. THere's absolutely no propellant blast from firing the weapon - and this is supposed to be a 120mm round firing off. Even if Shiro hadn't been pulverized by overpressure, he'd be cooked by the firing of the gun in all probability.

Add to the fact the shot is moving perfectly straight throught he atmosphere with no drop in gravity and you get the same problems you get with most sci fi zippy 'bolts'. But unlike something like Star Wars you can't really handwave miniature antigrav bullshit to excuse it in Gundam.

I don't see why I should start assuming it's some kind of robit magic ammunition propelled by pixie magic based on a singular example. And you can't have it both ways. If we assume the round is capable of traveling and having an effect at ranges up to several kilometers, you can either accept that this snippet has a gaffe in it and keep the rest or you toss it aside as not valid because the scene requires you to assume technology exists to make it plausible, in which case you're probably just getting a non consistent probably contradictory example of a robit gun in action, not to mention the implication that all robit guns work by magic.

And just as a side note, having no drop for the round is a common mistake made and trying to explain it is more often than not an exercise in futility. For the most part, we see x firing at y and the effect and I just assume the drop was corrected for.

In any event its pretty silly to generalize from one example, since in the very same episode you have gunfire traveling at multiple km/s (and in at least one other episode in that same series, with the Magella tanks.)

However you try to explain it, there's more to it than just SLOW BULLETZ LOLZ

Please, if I was trying to generalize I could dig up far more examples of robit guns having shitty performance than a single clip. I just assumed people had seen the whole piece where that clip was from and from that could get what I was saying.
And just so you know. Low power is not the same as slow bullet. If you can't figure this out on your own, just ask, I'll tell you.

-Gunhead

[Stark]

The only thing noteworthy about the event is lack of flash and blast; idiots might imagine it requires huge reflexes to leap aside from a shot that was going to miss anyway, but their inability to imagine Shiro seeing the Zaku pulling a trigger isn't my problem. Expecting me to give a shit about the one example everyone always brings up to make sweeping generalisations about UC projectile weapons just makes me lol at that poor guy. It's like imagining everyone is cloud chopping left and right. :v

[Connor MacLeod]

I don't see why I should start assuming it's some kind of robit magic ammunition propelled by pixie magic based on a singular example. And you can't have it both ways. If we assume the round is capable of traveling and having an effect at ranges up to several kilometers, you can either accept that this snippet has a gaffe in it and keep the rest or you toss it aside as not valid because the scene requires you to assume technology exists to make it plausible, in which case you're probably just getting a non consistent probably contradictory example of a robit gun in action, not to mention the implication that all robit guns work by magic.

Yeah see I tried arguing along the lines of 'we shouldn't read into every little bit of visual evidence' with that scene before on Spacebattles (General decided to resurrect a discussion from an old thread where it came up, and this is the same gif he used to claim Zaku bullets were so slow Shiro could dodge them even after firing.) and a bunch of people screamed over the idea because the answer MUST BE subsonic ammo.

The problem isn't explaining it. Its trivially easy to explain something in any number of ways. The problem is finding an answer people won't bitch over and/or can generally agree on, and one that doesn't shit over continuity (EG Assuming Gundam uses slow moving antigravity magic bullets.)

And yes you can say 'well other people are idiots' but they'll often say the same thing of other people's approach to dealing with fiction. I know, shocking that people will disagree over how fictional universes should be analyzed.

IT also doesn't help that opening up explanations like 'VFX errors' is a can of worms UNLESS you have some reasonable people who can achieve consensus and have no ulterior motives (EG people not like the SW vs ST debates.) because then anyone will declare VFX ERROR just on the basis that they, personally, find it inexplicable and can rationalize it no other way. Which has, of course, been done shitloads of times.

And just as a side note, having no drop for the round is a common mistake made and trying to explain it is more often than not an exercise in futility. For the most part, we see x firing at y and the effect and I just assume the drop was corrected for.

and if you can get people to afree on 'VFX error' as a reason that obviously works fine. But again the problem is not everyone is going to disagree for whatever reason, and can therefore degenerate into tons of tedious arguing over whose VIEWPOINT is more right.

Please, if I was trying to generalize I could dig up far more examples of robit guns having shitty performance than a single clip. I just assumed people had seen the whole piece where that clip was from and from that could get what I was saying.

You'd be surprised how oftne people want to generalize from isolated examples. It happened all the time in SW vs ST on both sides. As I said, its often more about people's perceptions of what is 'right' rather than what the evidence itself actually is, and its hard to avoid that sort of thing if it comes down to 'No UR WRONG! NO U R!' stuff. I don't know about you, but I find that sort of shit incredibly tedious now and find it simpler to avoid it where I can. If that means accomdoating other people's intransigence to some degree, I'm happy to do so.

And just so you know. Low power is not the same as slow bullet. If you can't figure this out on your own, just ask, I'll tell you.

-Gunhead

If you want to make suggestiosn go ahead. There are plenty of RL weapons that don't rely on velocity to do the damage, obviously, and there's no reason to assume mobile suit weapons are (always) dependent on KE as a primary/sole damage mechanism or they fire anti-tank rounds routinely or anything like that.

[Gunhead]

Yeah see I tried arguing along the lines of 'we shouldn't read into every little bit of visual evidence' with that scene before on Spacebattles (General decided to resurrect a discussion from an old thread where it came up, and this is the same gif he used to claim Zaku bullets were so slow Shiro could dodge them even after firing.) and a bunch of people screamed over the idea because the answer MUST BE subsonic ammo.

The problem isn't explaining it. Its trivially easy to explain something in any number of ways. The problem is finding an answer people won't bitch over and/or can generally agree on, and one that doesn't shit over continuity (EG Assuming Gundam uses slow moving antigravity magic bullets.)

And yes you can say 'well other people are idiots' but they'll often say the same thing of other people's approach to dealing with fiction. I know, shocking that people will disagree over how fictional universes should be analyzed.

IT also doesn't help that opening up explanations like 'VFX errors' is a can of worms UNLESS you have some reasonable people who can achieve consensus and have no ulterior motives (EG people not like the SW vs ST debates.) because then anyone will declare VFX ERROR just on the basis that they, personally, find it inexplicable and can rationalize it no other way. Which has, of course, been done shitloads of times.

Yeah. that's all true. But I'm extremely leery of the "we must assume X" way of doing analysis because then that becomes the magic pony that is used to justify outlandish claims of firepower or other abilities, usually by taking an event then using figures from it to claim ridiculously high power figures etc.

and if you can get people to afree on 'VFX error' as a reason that obviously works fine. But again the problem is not everyone is going to disagree for whatever reason, and can therefore degenerate into tons of tedious arguing over whose VIEWPOINT is more right.

Again, that is correct. But to add to my previous statement, we have to make some assumptions and those assumptions must have a basis on some fact either something we can derive from the series or RL considerations that might apply.

You'd be surprised how oftne people want to generalize from isolated examples. It happened all the time in SW vs ST on both sides. As I said, its often more about people's perceptions of what is 'right' rather than what the evidence itself actually is, and its hard to avoid that sort of thing if it comes down to 'No UR WRONG! NO U R!' stuff. I don't know about you, but I find that sort of shit incredibly tedious now and find it simpler to avoid it where I can. If that means accomdoating other people's intransigence to some degree, I'm happy to do so.

I know, and while some of this comes from simple assholeness, some of this is caused by the simple fact that people do not stop and think what they are looking at. When you're looking at a piece of fiction, the events are predetermined. You can do calcs to see what sort of energies were involved etc. But what is a lot harder, sometimes even impossible is to try and figure out how often things work out like they did. People can get into their heads that a single instance is how it will always play out, no matter what and will insist on it to no end.

If you want to make suggestiosn go ahead. There are plenty of RL weapons that don't rely on velocity to do the damage, obviously, and there's no reason to assume mobile suit weapons are (always) dependent on KE as a primary/sole damage mechanism or they fire anti-tank rounds routinely or anything like that.

Well my main point was that the velocity can be high if the round being fired is light. But if you're asking me to speculate further, that does look like a moderate velocity full bore round, probably rifled too if the swirls it leaves behind are indications of anything. If we take the clip as the bible truth.. well I have a few ideas but those are highly speculative.
The major problem is, that no matter what mr. roboto is spewing out, being that close to the business end is probably going to fuck you over. No amount of low velocity can explain it.
A HEAT round is low velocity, and those leave the barrel of a MBT somewhere around 800 m/s.

-Gunhead

[Stark]

If people keep assuming 120mm = 'just like a tank gun', can we play 'scale the gun off Shiro's body' and see what happens? In space, millimetres are clearly larger.

Don't worry, I'm not offended you ignore posts that suggest your repeated conclusions are wrong.

[Connor MacLeod]

Yeah. that's all true. But I'm extremely leery of the "we must assume X" way of doing analysis because then that becomes the magic pony that is used to justify outlandish claims of firepower or other abilities, usually by taking an event then using figures from it to claim ridiculously high power figures etc.

so let me rephrase then: depending on the methods of analysis being employed or discussed, we will invairably have to assume certain things, simply to maintain consistency. Exactly what must be assumed will vary, because not every approach will be the same, but there's still going to be a certain amount of consistency required for this shit not to become totally arbitrary.

And even then it STILL won't work if people can't reach some sort of consensus, because people trying to apply two completely different approaches will go nowhere. Ideally you try to opt for as many possibilities as possible, evne silly ones, because some people will only accept silly answers. It even doesn't even require one particular answer to be true in this case - all that really matters is pointing out that there is more than one alternative, rather than being a simple either/or scenario.

Again, that is correct. But to add to my previous statement, we have to make some assumptions and those assumptions must have a basis on some fact either something we can derive from the series or RL considerations that might apply.

True, but this again gets back to the approach one is using. We could, for example, cling strictly to visuals over dialogue the way 'traditionally' done with Star Wars (and to a lesser degree Trek, although some leeway is given there as in inconsistent ship sizes.) That however can lead to some real problems unless you bend over backwards or make compromises (much like trying to ratoinalize blaster behaviour/nature based strictly on visuals. Its a nightmare.)

Another possibility is to cling to dialogue or text - such as spinoff literature. This can have problems too, as the spinoff materials don't always quite mesh with the stuff in the animated shows (or with itself.) This gets into the dangers inherent in 'interpreting dialogue' which is made worse by the fact much of the dialogue/text is going to be translated (unless the person doing the analysis can read the language.)

A third approach is to take it on a case by case basis, and rather than adhereing to singular bits of evidence, cling to a more broader, generalized view of things. We know they have guns of a certain caliber that fire projectiles. We've seen cased ammo, rifling, fun stuff like that. We can make certain (rough) approximations based on that would guide us and treat the rest as outliers (stuff that is too slow or too fast.) Whether the outliers are ignored or treated as exceptions rather than the rule is up to personal preference/invidual case.

There's probably others, but each one will involve its own approach to the evidence and rules, each will have its own advantages and drawbacks, etc.

I know, and while some of this comes from simple assholeness, some of this is caused by the simple fact that people do not stop and think what they are looking at. When you're looking at a piece of fiction, the events are predetermined. You can do calcs to see what sort of energies were involved etc. But what is a lot harder, sometimes even impossible is to try and figure out how often things work out like they did. People can get into their heads that a single instance is how it will always play out, no matter what and will insist on it to no end.

Well yes, thats one way to look at it. But the problem is 'people don't stop and think' because whilst I've known plenty of people who adopt absurd or silly ideas, I've known plenty of people who are NOT stupid who do. And its very easy to get into disagreements simply because you cannot agree on how a single piece of evidence should be viewed. You can even encounter variations of even 'broad' approaches to fiction - some that will be inconsistent because people don't really bother or feel they NEED a consistent approach (or may call it 'over analyzing.')

The obvious question then becomes: how do you sort the people going on preconceived (and wrong) ideas from the people who simply have an honestly different perspective/interpretation of things, and don't hold to the way you view evidence?

Well my main point was that the velocity can be high if the round being fired is light. But if you're asking me to speculate further, that does look like a moderate velocity full bore round, probably rifled too if the swirls it leaves behind are indications of anything. If we take the clip as the bible truth.. well I have a few ideas but those are highly speculative.
The major problem is, that no matter what mr. roboto is spewing out, being that close to the business end is probably going to fuck you over. No amount of low velocity can explain it.
A HEAT round is low velocity, and those leave the barrel of a MBT somewhere around 800 m/s.

-Gunhead

Again alot of this comes down to how one figures alot of the gundamverse weaponry might work. There was a blurb on the 'Gundamofficial' site that mentions that machine guns (or at least the ones packed by the Zaku) were as powerful as a tank gun. Which seems pretty straightforward, but may not be. What kind of tank gun? Does it mean 'of the same caliber as the Zaku machine gun' or does it mean some other kind of tank gun? Is it impacted by other factors (size/shape of the casings, the barrel length, whether its full calibre/sub-calibre, etc.) Is it talking about KE and/or momentum, or something else? is it comparing individual shots, or is it 'sustained' firepower' or some variation (eg a single burst from the Zaku MG is equal in power to a tank cannon.) There's lots of variables involved in interpreting it, but all have the potential of significantly altering the outcome of the passage (and how it impacts the effectiveness of the weapon.)

And lets not forget that not all machine guns are the same, even when the calibres are the same. That alone can further add variation ot the case.

What's more, what about recoil? That's going to be a non-trivial issue and its one that sci fi analysis nerds all too often ignore. With solid propellant and cased ammo (lets say) there's going to be the recoil of the projectile.. PLUS the recoil of the propellant, and both for a tank gun is significant. Yet a mobile suit is supposed to be able to fire these guns with a pretty high ROF, yet that would multiply the recoil issues (and the problems with recoil) quite a bit if you assume high rates of fire. So recoil could quite likely result in individual 'machine guns' being less powerful per shot than tank guns, but perhaps comparable in power (but not necesarily other traits like penetration and such.) when taken as however big a burst you figure.

This is analogous to alot of flawed assumptions people make. Many 'sci fi' RTS/First or third person shooters feature guns or weapons with fictional calibers but closely resembling RL weapons, and its often assumed that .50 cal might mean (for example) 'equal in power to .50 BMG' which is a pretty erroneous thing to make, because there are lots of different .50 cal ammos, and there are also other factors (barrel length, again) affecting performance. (Recoil is often ignored in these cases too. The most hilarious being that an EM Gun used casings and propellant for the 'spin stabilization' in some hybrid setup.)

[Stark]

The 120mm is a space Lewis with a pan magazine; should we attribute it characteristics of a real Lewis with a man-scale pan magazine and say it jams or is bad in the field and Zeon abandoned it as terrestrial combat became an important concern? How far can those kind of 'looks like, is like' thought processes really go?

Doesn't change how we see the guns to operate. Should assumptions override evidence?

[Gunhead]

If people keep assuming 120mm = 'just like a tank gun', can we play 'scale the gun off Shiro's body' and see what happens? In space, millimetres are clearly larger.

Don't worry, I'm not offended you ignore posts that suggest your repeated conclusions are wrong.

Go right ahead. I used 120mm since some robit fan put it here and so far it's not been contested. Just make sure you scale the barrel of the gun. Because.. you know.. people might put oh I don't know.. a cooling shroud over the barrel to keep it from overheating. The thing is semi auto, and that usually translates to heating.
And while you're at it, scale the bullets too that come flying out when the magazine is hit. I'm sure you can make them look at least 300mm.

I was just ignoring your useless robit video and you not getting what I was saying. I clarified it to Connor. Which you also missed.
And really? A misfire? Sure, once maybe but twice in a row? Partial propellant burn can happen, but if you get two in a row you're the unluckiest SOB in known history. Or the luckiest in this case. So unless you can back this misfire theory with something solid like robit ammo having reliability problems, bad ones at that. I'm calling BS.

Overall, I compare things to stuff that they are similar to. The exact operating mechanism not withstanding, a robit gun that shoots really big bullets is pretty much like a tank gun.
A "tank gun" is a pretty fucking big category. 120mm and bigger pieces have been fielded since WWII on tanks and considering we are talking about a series that requires some amazing science it goes to sense you start off by doing comparisons with guns we put on tanks today and go from there.

-Gunhead

[Gunhead]

so let me rephrase then: depending on the methods of analysis being employed or discussed, we will invairably have to assume certain things, simply to maintain consistency. Exactly what must be assumed will vary, because not every approach will be the same, but there's still going to be a certain amount of consistency required for this shit not to become totally arbitrary.

And even then it STILL won't work if people can't reach some sort of consensus, because people trying to apply two completely different approaches will go nowhere. Ideally you try to opt for as many possibilities as possible, evne silly ones, because some people will only accept silly answers. It even doesn't even require one particular answer to be true in this case - all that really matters is pointing out that there is more than one alternative, rather than being a simple either/or scenario.

Yes, I think that pretty much nails it on the head.

True, but this again gets back to the approach one is using. We could, for example, cling strictly to visuals over dialogue the way 'traditionally' done with Star Wars (and to a lesser degree Trek, although some leeway is given there as in inconsistent ship sizes.) That however can lead to some real problems unless you bend over backwards or make compromises (much like trying to ratoinalize blaster behaviour/nature based strictly on visuals. Its a nightmare.)

Another possibility is to cling to dialogue or text - such as spinoff literature. This can have problems too, as the spinoff materials don't always quite mesh with the stuff in the animated shows (or with itself.) This gets into the dangers inherent in 'interpreting dialogue' which is made worse by the fact much of the dialogue/text is going to be translated (unless the person doing the analysis can read the language.)

A third approach is to take it on a case by case basis, and rather than adhereing to singular bits of evidence, cling to a more broader, generalized view of things. We know they have guns of a certain caliber that fire projectiles. We've seen cased ammo, rifling, fun stuff like that. We can make certain (rough) approximations based on that would guide us and treat the rest as outliers (stuff that is too slow or too fast.) Whether the outliers are ignored or treated as exceptions rather than the rule is up to personal preference/invidual case.

There's probably others, but each one will involve its own approach to the evidence and rules, each will have its own advantages and drawbacks, etc.

I think the more removed the series you're watching is from real life, it becomes more muddled since you have to take in what people say at face value, inconsistent descriptions of events and base calculations on less than solid sources. So that's when you'd have to use all three you've described there. At which point you basically have to achieve some sort of consensus what is considered "canon". If you can't then it will probably just degenerate into a shouting match with people trying to dig up examples of the most MEGATONNES!

Well yes, thats one way to look at it. But the problem is 'people don't stop and think' because whilst I've known plenty of people who adopt absurd or silly ideas, I've known plenty of people who are NOT stupid who do. And its very easy to get into disagreements simply because you cannot agree on how a single piece of evidence should be viewed. You can even encounter variations of even 'broad' approaches to fiction - some that will be inconsistent because people don't really bother or feel they NEED a consistent approach (or may call it 'over analyzing.')

The obvious question then becomes: how do you sort the people going on preconceived (and wrong) ideas from the people who simply have an honestly different perspective/interpretation of things, and don't hold to the way you view evidence?

Hmm.. That's a tough one. I think a person with a different perspective could see my point of view and how it fits the evidence while still holding his conclusions better. It really comes a matter of opinion then and at that point it's a case of agreeing to disagree. If someone holds a preconceived notion of something, he's probably going to be much more unwilling to see it from my perspective. Kinda hard to put your finger on it really.

Again alot of this comes down to how one figures alot of the gundamverse weaponry might work. There was a blurb on the 'Gundamofficial' site that mentions that machine guns (or at least the ones packed by the Zaku) were as powerful as a tank gun. Which seems pretty straightforward, but may not be. What kind of tank gun? Does it mean 'of the same caliber as the Zaku machine gun' or does it mean some other kind of tank gun? Is it impacted by other factors (size/shape of the casings, the barrel length, whether its full calibre/sub-calibre, etc.) Is it talking about KE and/or momentum, or something else? is it comparing individual shots, or is it 'sustained' firepower' or some variation (eg a single burst from the Zaku MG is equal in power to a tank cannon.) There's lots of variables involved in interpreting it, but all have the potential of significantly altering the outcome of the passage (and how it impacts the effectiveness of the weapon.)

And lets not forget that not all machine guns are the same, even when the calibres are the same. That alone can further add variation ot the case.

This is where it, to me at least, it becomes a numbers game. Saying that x is more powerful than y is less than useless when y is a broad category. Even if you'd make it x is more powerful than the U.S army M256 120mm tank gun, you're still not really telling me in what way it's more powerful. That's why you often see something described as more effective against x when you read professional material on weapon systems. The problem is, that in RL too we have several gauges to what is considered more effective. Something like grenade x having more explosive in it than grenade y is straight forward, but when you start looking at blast, shrapnel radius, penetration... it becomes a lot more difficult.
And that's why I honestly don't believe you can ever, in any fiction, reach a state where you can solidly explain everything about their weapons. The RL measurements for this stuff are not 100% and when you're analyzing fiction, you get slapped with less than stellar examples to draw data from, lots of singular instances and other stuff which basically reduces your analysis to the level of and educated guess. It can be a really really educated guess though if you can get enough to go on with or you can rule out the contradictory stuff.

What's more, what about recoil? That's going to be a non-trivial issue and its one that sci fi analysis nerds all too often ignore. With solid propellant and cased ammo (lets say) there's going to be the recoil of the projectile.. PLUS the recoil of the propellant, and both for a tank gun is significant. Yet a mobile suit is supposed to be able to fire these guns with a pretty high ROF, yet that would multiply the recoil issues (and the problems with recoil) quite a bit if you assume high rates of fire. So recoil could quite likely result in individual 'machine guns' being less powerful per shot than tank guns, but perhaps comparable in power (but not necesarily other traits like penetration and such.) when taken as however big a burst you figure.

This is analogous to alot of flawed assumptions people make. Many 'sci fi' RTS/First or third person shooters feature guns or weapons with fictional calibers but closely resembling RL weapons, and its often assumed that .50 cal might mean (for example) 'equal in power to .50 BMG' which is a pretty erroneous thing to make, because there are lots of different .50 cal ammos, and there are also other factors (barrel length, again) affecting performance. (Recoil is often ignored in these cases too. The most hilarious being that an EM Gun used casings and propellant for the 'spin stabilization' in some hybrid setup.)

While recoil would be an issue, we rarely get good enough data to really gauge the effects on joints, recoil absorbers etc. To really evaluate this, we'd need some solid non derived data on the materials used on the robots / vehicles, which we rarely do. That's why we're stuck with for the most part just accepting the "well it didn't break, I guess it's tough enough" approach. Same goes for exotic ammo / propellant etc. We can only really gauge the effect it has and then draw some conclusions on the exact type of the round and so forth. In a sense, the assumption that say a .50cal round in scifi is the same as ours is both wrong and correct. It's wrong because we might not know what the round is made out of, what's the propellant etc. It's right in the sense that it's a good place to start your comparison with. All and all, I think here too the problem is what I referenced earlier. Penetration figures etc. are not 100% accurate and again if you slap on all the baggage that comes with analyzing a piece of fiction, you are can get estimates and that's about it.

One of the more neglected aspects is heat. All guns cause heat and with big automatic guns, that becomes a major issue really fast. I'd peg that above recoil when it comes to non trivial issues we get in scifi all around but specially in robit stuff.

-Gunhead

[The Yosemite Bear]

my hiver kenetic kill missiles wipe both of them mammals

[Zinegata]

Yeah see I tried arguing along the lines of 'we shouldn't read into every little bit of visual evidence' with that scene before on Spacebattles (General decided to resurrect a discussion from an old thread where it came up, and this is the same gif he used to claim Zaku bullets were so slow Shiro could dodge them even after firing.) and a bunch of people screamed over the idea because the answer MUST BE subsonic ammo.

What's wrong with subsonic ammo in the first place?

Again, it bears remembering the gun was originally supposed to be used in space against relatively stationary battleships. Subsonic ammo with little casing and huge amounts of explosive content (making it a powerful HE or HEAT round) makes a fair amount of sense in this setup; especially since it will greatly minimize a lot of the heat and wear issues with the barrel.

There are, in fact, good reasons in real life why you don't want as much kinetic power as possible into each of your shots.

And do note it doesn't prevent the 120mm having different types of ammunition, which explains other cases where the 120mm doesn't act the same way. You were on to something when you asked if beam rifles could be affected in different ways by atmospheric (or even deliberate disruption) factors to explain away the differences in beam rifle performance. Why not assume the problem in this case is with the ammunition and not the gun?

[Stark]

Since the gun doesn't even look to be aimed at Shiro and he would have seen the trigger being pulled, Connor is probably just saying using poor reasoning for a conclusion is poor. 120mm are certainly seen sometimes with pretty slow projectiles and a lot of arcing (there's a brief shot in that clip where Keith fires a 120 for instance) but if people are saying SHIRO NOT INSTANTLY SET ON FIRE BY GUN THAT APPEARS TO BE TWO FEET WIDE SOMEHOW = ALL GUNDAM GUNS BAD are not rational people, and the statement includes a whole lot of assumptions.

Like 'fired twice' because a huge car-sized yellow rectangle came out followed by a cloud of yellow triangles.

[Zinegata]

Since the gun doesn't even look to be aimed at Shiro and he would have seen the trigger being pulled, Connor is probably just saying using poor reasoning for a conclusion is poor.

Yeah, I kinda got that, but again my question is what's wrong with the subsonic ammo theory on its own based on the discussion he had? It's not as though subsonic ammo automatically makes the gun useless - if you want a shell with a lot of explosive power you actually benefit from using a subsonic shell. Subsonic round means the casing doesn't have to be as strong, so you can pack in more explosives.

I'm not saying subsonic ammo is the right answer or the only answer, but I'd really like to hear what are the counter-points to it being the answer.

[Stark]

I'm not confident in my ability to eyeball 'subsonic', but since 120mm blow up tanks, throw up 15m dust clouds etc, if they're slow explosive rounds I don't really see how this is 'bad'. I'm only familiar with the 'reasoning' that since the 120mm in this example has 'no flash' and is 'really slow', this means all Gundam guns use WORSE THAN BLACK POWDER OMGZ.

And I know that people don't like a lot of evidence with their robits, but I was wondering about something after talking to Connor. It seemed to me that the 120 was shown to have a much larger bore than usual, so I made some more of that 'useless' evidence stuff from that irrelevant primary source material. :V


I happen to have a Zaku lying around, and even with the elbow cocked a bit to contact the ground, the hand is still about waist-level. The gun is pretty long. Shiro is shown to be standing at or near the knee of the prone Zaku. I think it's either Zeon's secret Telescoping Gun with Variable Barrel Geometry (note in particular the ratio foregrip:barrel in the images) or the show has some 'camera' 'lens' effects going on. I'm not really down with how things like depth of field work, but if this is the one example to define Gundam guns or even the 120 (or even THIS 120) its a piss-poor one.

In the same scene, we have this example of a 175 tank gun being used



Note the violent muzzle blast throwing a projectile at perhaps several kilometers per second. JUST LIKE A TANK GUN AM I RIGHT

Because I enjoy using facts and sources to ruin idiots, I tried to get a good shot of this mark of 120 firing to get a read on its muzzle flash, but in my quick look I could only find one being fired off-shot and thus you can't see its full extent. It's only a few times wider than the gun barrel (and not a cataclysm of godrays like the 175) but you can't see how long it is. Oh well; Gunhed will just ignore it anyway. It's pretty sad that using evidence from the shows people are talking about make this so easy, when people are happy to talk in circles based on nothing for so long.

PS Zinegata agreeing with you is pretty unsettling.

[Gunhead]

Since the gun doesn't even look to be aimed at Shiro and he would have seen the trigger being pulled, Connor is probably just saying using poor reasoning for a conclusion is poor.

Yeah, I kinda got that, but again my question is what's wrong with the subsonic ammo theory on its own based on the discussion he had? It's not as though subsonic ammo automatically makes the gun useless - if you want a shell with a lot of explosive power you actually benefit from using a subsonic shell. Subsonic round means the casing doesn't have to be as strong, so you can pack in more explosives.

I'm not saying subsonic ammo is the right answer or the only answer, but I'd really like to hear what are the counter-points to it being the answer.

The reasoning is this. The danger to a person standing in front of a cannon is not the round exiting the barrel primarily. It's the overpressure created by the expanding gasses coming out behind it. Now, some people deduct from this the Zaku ammo must be subsonic because otherwise dogdeboy would be torn apart. I don't think so since subsonic is under the speed of sound but still going around 300m/s and this is more than enough to create overpressure, which might be more survivable but you'd still get internal bleeding, burst eardrums and generally you'd not be feeling well, possibly it could be fatal.
Note: 300m/s is the round exiting the barrel, the gas coming out would be a bit faster if I remember correctly. I can't be bothered to dig out the numbers right now. The danger zone typically is roughly the 45 degree zone in front of the barrel and if it's a APFSDS round, it can extend up to 200m. For a HEAT or HE round it would probably be less, but it's pretty safe to assume if you're standing within 50m of the barrel, you are in serious danger of being mushed. This with modern day ammunition mind you.
This is why I was in favor of dismissing the whole incident as an outlier because no matter how low powered the Zaku gun is, it's still using some sort of chemical propellant to drive the round out of the barrel and this would be nasty for anyone standing so close to it. If we must take that clip as the bible truth, it takes a ton of magic tech / handwaving to make it plausible.

The drawbacks of subsonic ammo are primarily it takes for them ages to reach a target at range. That's about 3s to 1000m, 6s to 2000m and so forth, not counting for slowing down due to drag, arcing etc. For the purposes of vehicular combat, they're way too slow when you consider typical ranges are from 2000-3000m today and more depending on the weapon system used. You did see some pretty big low velocity HE sluggers like the Churchill AVRE in WWII to smash bunkers, but weapons of that type aren't useful anymore as we have more accurate, long range ways of chugging HE around. This is why HE / HEAT tank rounds have exit velocities of around 800m/s because that's the most the fusing mechanisms can handle, unless there have been some major advances in that field I'm not aware of.

And Stark, read this. I used small words with just a few abbreviations for your benefit.

-Gunhead

[Stark]

Sorry I can't hear you over the radio saying 'if we take the clip involving a hugely foreshortened and distorted gun as bible truth'.

I'll set you a fun homework assignment; actually demonstrate the dangers of muzzle flash. I don't doubt they exist; but you have provided no reason to actually accept the existence of a danger that needs to be handwaved. I know evidence isn't a big thing for you, but I'm sure you can google it.

Nice irrelevant trivia, though!

[Zinegata]

I'm not confident in my ability to eyeball 'subsonic', but since 120mm blow up tanks, throw up 15m dust clouds etc, if they're slow explosive rounds I don't really see how this is 'bad'. I'm only familiar with the 'reasoning' that since the 120mm in this example has 'no flash' and is 'really slow', this means all Gundam guns use WORSE THAN BLACK POWDER OMGZ.

Uh, are you that retarded? Where in my argument did I say Gundam guns use "WORSE THAN BLACK POWDER?" When did anyone do this? Perhaps the part where you can't comprehend that low velocity rounds is sometimes better depending on the type of weapon you're aiming for, so you instead pretend it's some other argument?

You do also realize that a low-velocity round with a lot of HE and HEAT explosive can in fact blow up tanks, and they're better at making 15m dust clouds than a pure kinetic energy shell, yes?

If you can't wear your grown up pants, then stop spouting nonsense. This is really going to devolve into your friends needing to cover up your blatant trolling again by pretending that no one outside your clique has made an argument.