Refleks said:

No, there is definitely enough room for my assertion...

The armadillo's seating arrangement obviously places the commander and gunner into the hull taking up just as much swept floor area as the turret basket did (you can even see the circular outline of where the turret would have been in the digital cutaway)...

In the second video I linked, the commander and gunner seats appear to be further forward than shown in the digital cutaway, placing the commander right up against the front wall, but still with insufficient space to add another passenger seat behind him.

It looks to me like your assertion is iffy at best.  Your conclusion is based on a simplified line drawing that does not show every detail.  The video of the actual vehicle interior makes it appear somewhat doubtful that it is practical to install another passenger seat.

RovingPedant said:

Most concept/new AFVs usually mount quite a few,

Concept and prototype do.
There are few in service.
The question also is why are they sticking cameras on everything in large numbers? Not because it is usefull or improves anything. Its cheap. It also appears high tech and fancy.

RovingPedant said:

Things change and you have to revisit concepts with an open mind once in a while to find out if the reason is still valid

True but its also not an end to itself. The miniguns is a bad concept to start with. Has been back in the day when it was developed and still is. Now arguing to not use what the gun has been intended for and doesn't do very well to do something it has not been developed for and as a result does only very bad is not revisiting. Its trying to shohorn a bad solution into another problem in an attempt to... to do what really?
If the manufacturer had suggested it I would get it. They want to sell more stuff. Sobody with no affiliation?

RovingPedant said:

Isn't the barrel change procedure for the MG34 to pivot the receiver about a pivot parallel to bore axis and withdraw the barrel directly backwards, while the MG42 requires space alongside the barrel shroud since the barrel comes out sideways, pivoting somewhere about the muzzle device?

Yes.

RovingPedant said:

Surely this means that the MG34 could be mounted further through an armour plate,

The barrel shroud of the MG42 has a bigger diameter compared to the MG34. Without redesign they will not fit trough the same opening anyways.
 

The space you need to change the barrel of an MG34 or MG42 is more or less the same. But in different places. As you say the MG34 if mounted pivots the receiver out of the way and the barrel goes straight back. But the receiver needs to pivot somewhere. This includes the firing group, pristol grip, belt feed and gets a fiddly if there still is a belt connected to the feeding.
The MG42 has the side port. There is not really a pivot point. The barrel is moved to the side so the locking block clears the gun and is then pulled allmost straight back in paralel to the gun. So basically on the right side you need enough space for the barrel to get out of the gun and a little more for a hand to grab it. That is a far more efficient arangement than that of the MG34. Generally speaking and especially if used from bipod.

RovingPedant said:

particularly for bow gunner positions.

irrelevant since I am argung for coax use and allmost no modern vehicle has such a mount or anything similar.
In the case of the MG42 the ball mounts would have had to be redesigned too. The continued use of MG34 in AFV especially tanks is because they did not want to redesign, the gun offered specific advantages the way it was used and it worked good enough.
BTW the coax version of the MG34 had a special modified barrel sleeve. It was not the same as the GPMG version.

RovingPedant said:

One case that shows that one of the main objections for the use of miniguns no longer exists.

One case that shows a specific group of people (or even only one persone) does so.
BTW what would be the main objection? The main objections are that a minigun is an inefficient design and as a result to large and heavy, its inaccurate and needs electrical power. None of these would be adressed by changing the ROF. As mentioned quite the oposit. Since the only pro a minigun has is the ROF the only reason to use such a gun at all would disappear.

RovingPedant said:

If you need to change the barrel, then overheating is an issue that needs to be addressed in one way or another.

Yes. But there are far better, more efficient ways to do so instead of using a minigun.

RovingPedant said:

That RLS even prototyped the 3-barrel auto-change thing suggests that weapon overheating is a concern.

No necessarily. It only shows that they predicted that it could be a concern and wanted a product to offer should this happen.
The thing is the RWS GPMGs overheating had been a problem caused by the specific conditions. Mostly the absense of more powerfull guns and fire support options. Once .50, 40 mm AGL and 20 mm ACs had been fielded as well as 155 mm indirect fire support made available the need to use GPMGs as main and only asset dissapeared. The time length of typical engagements went down significantly as well. All of a sudden overheating ceased to be an issue. More or less the same as it happened with the G36.
The problem was not overheating guns and it could not have been solved by making the guns withstand more heat. The issue had been desisions made at higher levels and the lack of appropiate weapons. MGs that would have endured longer would not have solved anything.

RovingPedant said:

Few if any RWS feature protection for the gun,

That is not coax use.
But I would still argue that a low ROF minigun is a bad choice.
 

RovingPedant said:

If we're considering auto-change barrels on an MG3 or various exotic calibres, why not?

So the argument is: if only bad and outright stupid suggestions are on the table, why not thing about a low ROF minigun as well?
Not the way I think about solutions but now I get it. Good and effective solutions are out and only the rest is to be concidered. In this case a low ROF minigun fits very well.

Refleks said:

No, there is definitely enough room for my assertion, you can see a scale cutaway and seating arrangement / turret basket here.

You have to be terribly carefull in the case of the CV90.
There different version differ quite a bit. The original Swedish version with 8 seats for dismounts do not have modern blast protection. As a matter of fact few CV90 do have these. This simply has not been a thing when the CV90 had been developed. If they are uprgaded and equiped to higher standarts the number of seats goes down. The improved Swedish versions loose one seat. The Mk IV is a substancial improvement but still not on the same level as more modern vehicles. There is a limit to what can be achieved with a given size and weight.
This is why they came up with the Armadillo version of the APC version. As a COIN/LIC vehicle with full scale modern protection at the expense of firepower. This is why the Armadillo "only" seats 7+2.
What a lot of people forget is that blast protection doesn't only mean portected seating a spall liners. It also means each and every bit of gear has to be stowed in a way it can not be ripped loose and becomes a danger. This means you need space for the equipment and personel gear as well. This eats up a lot of volume. Its visible on the Armadillo drawing for example. The "gaps" are not empty in reality. This is storage space.

The question is kind of vehicle does Elbonia need. If COIN and LIC is off the table this increases the number of options. As does if they don't care for their soldiers to the same degree as other nations do.

There also is the question if its a good idea to cram many soldiers into one vehicle. 10 allready is an awefull lot.

Original CV90 , was armored less than BMP2 , was real low budget IFV with minimal features CV90 was back then probably inferior to all major IFVs used in NATO. Todays CV90 MK III & MK IV have very little in common with the original 

is a simplified line drawing but it's also from hagglunds and is accurate. I've seen the turret basket and ammunition stowage underneath and there is definitely room for 2 more seats on each side (facing inwards, not facing forward) if the turret and ammunition storage were not present, which should not be surprising considering the swept area of the turret basket takes up a good volume and there are two people already inside, meaning minus turret you can only fit two additional people. This is not iffy, it's entirely reasonable.

Recall the discussion went like this
1. I said you could fit more in a CV90 without turret (so if someone was scratching their heads about squad sizes and dismounts that there were some other potential options possible)

2. Someone responded you couldn't because Armadillo can't therefore it's not possible

3. A variety of reasons were presented as to why Armadillo cannot; ie, if it had individual shock mitigating seating, and because two of the seats are oriented forwards rather than inwards

That doesn't mean my assertion is incorrect - if you didn't have shock mitigating seating and if the seats were oriented inwards you could fit more inside. I'm not saying we ought to go that direction, I was just saying it's a possibility.

schnuersi said...

irrelevant since I am argung for coax use and allmost no modern vehicle has such a mount or anything similar.

I'm building the case that vehicle mounted single barrel MGs usually have provision to change the barrel, presumably because you need to change the barrel

schnuersi said...

BTW what would be the main objection? The main objections are that a minigun is an inefficient design and as a result to large and heavy, its inaccurate and needs electrical power. None of these would be adressed by changing the ROF. As mentioned quite the oposit. Since the only pro a minigun has is the ROF the only reason to use such a gun at all would disappear.

A minigun weighs 26kg*. The (electrically powered) L94A1 chaingun weighs 18kg plus a spare barrel. The barrel change RMG 7.62mm weighed 35kg.** Fire control requires electrical power.

If you need a weapon that is located somewhere that you cannot manually change the barrel and the barrel change RMG is a consideration, then the externally powered gatling that is the minigun is an alternative because it spreads the heating out over six barrels so you can fire at the same rate without having to change a barrel for heating concerns.

schnuersi said...

If the manufacturer had suggested it I would get it. They want to sell more stuff. Sobody with no affiliation?

The manufacturer is selling their gun on their RWS for land vehicle use. I kind of like the concept for a remote gun and the only show-stopper I can see is the increased dispersion and cost.  

schnuersi said...

Yes. But there are far better, more efficient ways to do so instead of using a minigun.

Such as?

* 32kg with the gun control unit, but that doesn't need to be in the same place as the gun.

** https://s3.ap-southeast-2.amazonaws.com/uat.2dm.digital/rheinmetall/attachments/2021/5/1621391598695Rheinmetall%20Machine%20Gun%20RMG%207.62.pdf

Refleks said:

if you didn't have shock mitigating seating and if the seats were oriented inwards you could fit more inside. I'm not saying we ought to go that direction, I was just saying it's a possibility.

Is there any point in _not_ having shock mitigating seating these days? And I think it usually faces outwards since it is suspended from the roof?

Also, if we can squeeze 1 or 2 more in, for 3+8, we'd be at a nicer section size

graylion said...

Is there any point in _not_ having shock mitigating seating these days? And I think it usually faces outwards since it is suspended from the roof?

Most personnel carriers have inward facing seats so they can share legroom and dismount easier. The seats are still mounted to the roof, or sometimes the wall. In terms of shock mitigation centre of the roof would be best, but it's only a matter of a bit more shock absorption between the inside and outside.

What often takes up more room is the stowage associated with each seat or spacing them out so that two 95th percentile men can sit next to each other.

Regarding reasons not to opt for shock mitigation: Sure, it depends on what you want to emphasize, what your doctrine and concept of employment is, what the threat is, how you mitigate risk and what tradeoffs you want to accept.  

Even before shock mitigating seating the number of dismounts for IFVs was compromised compared to an APC simply because the turret takes up space.

Now you can choose between more dismounts (back up towards more effective squad sizes) AND a medium caliber cannon, or the same number of dismounts with shock mitigation. Which goes back to my post over on the Elbonia thread: what do you want?  Do you want light infantry capable of fighting independently of the AFV, or do you want a small detachment intended to only fight with their direct support? Or do you want both? 

If we decide to go both, do you compromise on squad sizes for the sake of the limitations of the AFV, or refuse? Do you opt for larger vehicles, same sized vehicles without shock mitigated seating, or simply more vehicles in a platoon to carry all the people?  It's not straightforward.

RovingPedant said:

I'm building the case that vehicle mounted single barrel MGs usually have provision to change the barrel, presumably because you need to change the barrel

If you want to build the case around such a broad statement you would have to define "provision to change the barrel" and "need to change".

Because I would callenge that. Lots of vehicle mounted single barrel MGs do not have this. The vast majority of RWS do not. Remote controlled turrets have not. All .50 cals don't. For the simple fact that even though its called QCB its by no means quick and convenient to change the barrel of an M2. At least not compared to the vast majority of GPMGs used on vehicles. For me a QCB must be as quick and easy to change as in a MG3, FN MAG or PKM. If the M2 qualifies lots of 20 mm cannons do as well.
From my point of view the vast majority of rifle caliber machine guns mounts, mounted under armor protection and reachable by the crew of a purpose build AFV do allow for barrel change. Lots of pintle mounts do as well or better don't interfere with barrel change. But that is about it.

I have been talking specifically about coax mounting. I am willing to broader my arguments to the above. The arguments I listed and will list would still be valid.
I am not talking about remote controlled use. This is different. That doesn't mean I think a minigun is a good choice for that unless the ROF is desired but the arguments are different and some of what I wrote would become invalid.

RovingPedant said:

A minigun weighs 26kg*. The (electrically powered) L94A1 chaingun weighs 18kg plus a spare barrel. The barrel change RMG 7.62mm weighed 35kg.** Fire control requires electrical power.

Weight is not the issue.
For use under armor volume is. A minigun is big. Also the entire barrel cluster would need the be at least partially outside. Resulting in a significant hole in the armor.
In additon because of the poor accuracy more ammo is needed for the same effect. Further increasing the required volume.
The beatuy of the L94/chaingun is that it is very compact. It basically offers the advantages of a minigun in a much smaller and more convenient package. At the same time it doesn't have the same drawbacks.
The RMG doesn't really exist so IMHO it should be ignored. It also has specifically been developed for use in RWS.

If barrel change is required and if yes how often is the question. Since in AFV with manned turrets coax guns usually are reachable there has been no need to use specialised gear. The standard issue GPMGs with some standard spare barrels do just fine.
Even in coax use the ready to use ammo supply is usually 500 rds or less. Sometimes 1000 rds but more often than not its a second 500 rds bin that allows for quick belt replacement. Which also needs interference by a crewmember. So in a worst case scenario a MG mounted inside a vehicle can fire 1000 rds in one long burst. If this would be concidered a necessity or real problem heavy barrels or barrel with cooling of some sort that allow for 1000 rds to be fired trough them in one long burst would be issued. For a long time. If the problem became a thing recently we would see a recent move in this direction. But we don't. What we see are some militaries issuing heavy barrels with somewhat more heat capacity.

In RWS the number of ready rounds is usually even lower. So at best it would be an issue for the RWS mounts that can be reloaded under armor but barrel change can not be done. Even here we don't really see any serious development to solve "the problem". A couple of years ago concept like the RMG poped up but found not takers. Some heavier barrels are issued now by some. For most part we see an increase in weapon size. RWS moved aways from GPMGs to HMGs and 40 mm and now there is a conciderable move towards ACs. In some cases with additional GPMGs as secondary.

RovingPedant said:

If you need a weapon that is located somewhere that you cannot manually change the barrel and the barrel change RMG is a consideration

I am not a fan of the RMG concept but its still is conciderable superiour to a minigun. Its accurate!
An actual sensible solution would be to mount a second GPMG with half of the ammo. Two MG3 don't weight 36 kg. Alternate using would allow for at least double the number of rounds fired. If high ROF is need (anti drone) both could be fired at the same time.
Light weight, only needs minimal power, accurate and no new equipment is needed. Of course the same could be done with an FN MAG or whatever GPMG.
BTW this used to be the solution picked in the past for cases when MGs had to be mounted on AFV that could not be directly serviced by the crew.
The Strv has two FN MAGs mounted in a box on its bow.

RovingPedant said:

I kind of like the concept for a remote gun and the only show-stopper I can see is the increased dispersion and cost.  

...and it is massive.
Miniguns are only usefull if you need lots of shots downrange fast, for a significant time and if its not important that most shots will miss and that it might take a couple of dozen rounds fired until a hit is scored.
Which makes it a poor or even impossible choice for most uses.

RovingPedant said:

Such as?

As mentioned: use two GPMGsor a purpose designed barrel.
A cooling device is also an option.
Even for high ROF a minigun is not the most efficient option. High rates of fire can be reached by other gun designs without the volume and dispersion of a minigun.

RovingPedant said:

* 32kg with the gun control unit

For 39 kg you can get a 20 mm AC. Or 3 MG 3 for ~34 kg.
3 MG 3 would allow for 750 rds of continous fire under peace time regulation if used one after the other. Or if they all fire at the same time match the ROF of a minigun. While having much less dispersion and being self powered.

Unless you want to fire several hunderets or thousands of rounds very fast and have no problems with volume and ventilation I really see no need for a minigun.