stancrist said:

What you are doing is hypothesizing an alternate universe wherein the generals and military police are somehow magically forced to swap their pistols for MP7s

Yes exactly. I am presenting my opinion. What I would do if I could decide.
Because if I can decide why compromise? If the paradigm is that I can not decide then my opinion and any discussion is pointless.

stancrist said:

Shoot, I could hypothesize an alternative challenge wherein both 9mm and 4.6mm are eliminated,

Sure.
The think is IMHO the small arms and amunition western armies commonly issue and use make little to no sense. Its basically leftovers, tradition and the cheapest way. So from my point of view the entire system needs to be rethought.
BTW i am not convinced that 4,6 or 5,7 are the optimal choice. I also agree that two so similar cartridges are unnecessary and also just a relic of traditional "not invented here" thinking. They are just what is widely available now. But I do think the general layout and design of the MP7 is good. If a MP7+x that is somewhat smaller and uses different ammo would come around that would certainly be better. The 7.5 FK looks intresting. But its conciderable more powerfull than the 5,7 or 4,6. This is intresting for armor penetration though.

stancrist said:

As I see it, the only folks who really need a PDW like the MP7 are tankers.

And I see it the other way round. Exept for infantry men, to be really exact, the guys who actually fight dismounted, nobody needs a rifle or a carbine. They can all be equiped with PDWs. The rifle is a specilist weapon and very niche. The vast majority of just need PDWs and GPMGs.

stancrist said:

Replace conventional tanks with a Merkava type,

So you want to compromise the effectiveness of the ground forces main weapon system so the crews can be equiped with a carbine... that makes no sense at all.

Depends on the PDW. If you're looking at an M1 carbine type weapon (that would include M4/AK-74AKSU and such) it can be used in drawn out firefights. An MP7 type weapon, no.

The reason that an MP7 (when used as a PDW) can't be used in prolonged firefights is because of the small quantity of ammo that would normally be carried on the person.

MP7

3 x 20 rds = 60 rounds

or

1 x 20 rds + 2 x 40 rds = 100 rounds

----------

Used as a PDW, an M4 variant would have a comparable ammo supply.

M4

3 x 30 rds = 90 rounds

schnuersi said:

       stancrist said: As I see it, the only folks who really need a PDW like the MP7 are tankers.

And I see it the other way round. Exept for infantry men, to be really exact, the guys who actually fight dismounted, nobody needs a rifle or a carbine. They can all be equiped with PDWs.

Certainly, they can be equipped with PDWs.  However, they also can be equipped with rifles or carbines, just as they were in World War II. 

Cooks, clerks, mechanics, generals, artillerymen, helicopter pilots, and others do not truly need a PDW that is as small as the MP7 or MP9. 

schnuersi said:

       stancrist said: Replace conventional tanks with a Merkava type,

So you want to compromise the effectiveness of the ground forces main weapon system so the crews can be equiped with a carbine... that makes no sense at all.

How would it compromise ground force effectiveness by changing the configuration of tanks from rear engine to front engine?

stancrist said:

However, they also can be equipped with rifles or carbines, just as they were in World War II.

During WW2 no army that I am aware of did equip their AFVs with rifles. Only the US issued carbines (since no other nation had a similar weapon).
The German army did issue SMGs. But the most universal issued small arm for AFV during WW2 have been pistols or none at all.

stancrist said:

How would it compromise ground force effectiveness by changing the configuration of tanks from rear engine to front engine?

The engine in back layout is inefficient. It creates a higher hull, causes difficulties in armoring the front, results in exposed air intakes and exhaust, has negative impact on the gun elevation in the frontal arc etc. The list goes on.
There is a reason why on one nation has build an MBT with this layout. It was tried time and again by everyone else and found inferiour. The Merkava is a very special vehicle. Its optimised for the tactical and operational situation of Israel and for the terrain there. This means the Merkava is conciderable less usefull everywhere else. Which is why nobody was ever intrested in buying it or building it in license. Its simply not a good layout for the requirements of the vast majority of tank building nations.

schnuersi said:

       stancrist said: However, they also can be equipped with rifles or carbines, just as they were in World War II.

During WW2 no army that I am aware of did equip their AFVs with rifles.

I meant all of the non-infantry types except tank crewmen.  Only tankers need a compact PDW.  All others can be armed with rifle, carbine, or SBR.

stancrist said:

I meant all of the non-infantry types except tank crewmen.

Make that vehicle crewmen and i agree... but then you have allmost everybody exept infantry.

stancrist said:

All others can be armed with rifle, carbine, or SBR.

There are lots of people in an army that do not need a rifle and for whom a carbine would interfere with the main task.

And yes during WW2 allmost everybody carried a rifle which lead to a lot a situations where non infantry personel got caught without any weapon at hand because a rifle is to large and unwieldy to be carried around all the time while doing something other than being an infantry man. The US came up with the carbine because they realised this. The carbine is still to large for most tasks.

schnuersi said:

       stancrist said: I meant all of the non-infantry types except tank crewmen.

Make that vehicle crewmen and i agree... but then you have allmost everybody exept infantry.

LOL.  There are a great number of soldiers who are neither infantry nor AFV crewmen.  Army MOS List: Full List of Army Jobs - HoodMWR

schnuersi said:

       stancrist said: All others can be armed with rifle, carbine, or SBR.

There are lots of people in an army that do not need a rifle and for whom a carbine would interfere with the main task.

Such as?

schnuersi said:

And yes during WW2 allmost everybody carried a rifle which lead to a lot a situations where non infantry personel got caught without any weapon at hand because a rifle is to large and unwieldy to be carried around all the time while doing something other than being an infantry man.

Can you cite any examples?

stancrist said:

LOL. There are a great number of soldiers who are neither infantry nor AFV crewmen.

No but they are vehicle crew... allmost everybody drives around in a vehicle and most task are even conducted while in the vehicle. If the vehicle is armored or is unimportant.

stancrist said:

Such as?

Engineers, medics, artillery men, signals guys, mechanics the list goes on.

stancrist said:

Can you cite any examples?

For non infantry soldiers getting jumped while they did not have a rifle nearby?
In the training manual of the German army used to be such examples. It also was a common occurence during training. People who where issued rifles frequently left them in their vehicle or put them somewhere where they would not get lost and ended up being unarmed in a supprise contact.
But you can easily google pictures of basically any German support arm during WW2 and usually you see a peculiar absent of small arms when the non infantry soldiers do their work. For example artillery, AA gun and AT gun crews.

schnuersi said:

       stancrist said: LOL. There are a great number of soldiers who are neither infantry nor AFV crewmen.

No but they are vehicle crew... allmost everybody drives around in a vehicle and most task are even conducted while in the vehicle. If the vehicle is armored or is unimportant.

Well, if you're going to define "vehicle crewman" as any soldier who drives a motor vehicle at some time during the year, then that means even infantrymen are vehicle crewman and should have a PDW instead of a rifle or machine gun...

schnuersi said:

       stancrist said: Such as?

Engineers, medics, artillery men, signals guys, mechanics the list goes on.

US Army medics are armed with a carbine, but it does not seem to impede them in performing their duties. 

And I see no reason why a carbine would be any more incompatible with the other jobs than would an MP7.

schnuersi said:

       stancrist said: Can you cite any examples?

For non infantry soldiers getting jumped while they did not have a rifle nearby? In the training manual of the German army used to be such examples. It also was a common occurence during training. People who where issued rifles frequently left them in their vehicle or put them somewhere where they would not get lost and ended up being unarmed in a supprise contact.

I meant examples from combat.  Peacetime training exercises don't matter.  In peacetime, soldiers do stuff they probably wouldn't on the battlefield.  During one deployment to the National Training Center, some of the guys in my battalion stowed folding beach chairs and coolers full of beer in the bustle racks of their tanks, then "kicked back" and relaxed with a cold brew in the evening.

schnuersi said:

But you can easily google pictures of basically any German support arm during WW2 and usually you see a peculiar absent of small arms when the non infantry soldiers do their work. For example artillery, AA gun and AT gun crews.

That's not even a little peculiar.  That's actually quite typical.  You see the same absence of small arms in most WW2 photos of US artillery in action.  For example:

It's still the same in the 21st century.

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