renatohm said:

He's using a sabot.

I used that term somewhat ironically. I mean a bullet that stays together when it hits a soft target, but discards the hardened steel core when hitting armour. That is why I put "sabot" in quotation marks. And my cartridge has significantly better external ballistics. IMO it is a decent successor to the M1 carbine. Which was used by REMFs and at reasonable ranges. Precisely because handguns were insufficient as proven in WWI. So my gun can reach as far as an M1 Carbine or more, has a bit more energy than .30 Carbine, can perforate at least up to IIIA, if not III armour and can be carried as a somewhat unwieldy handgun, while having a folding stock of probably something like 14" length, which, unfolded, should turn it into a reasonable carbine.

Like I said the practical hit probability at 300m,  for typical PDW-type personell,  is zero. You could change that by squeezing in a longer 12 inch barrel with reverse feeding. 

If you Downsized the caliber,  the saved weight could be spent on an integrated optic with a long 4x zoom.  Then it would be a 300m gun.  

How about considering 556 in a mini bullpup.  The logistical savings would make it more appealing to militaries 

PDW is meant for use well under 100m . No point in trying to make it effective to 300m although you can hit man-sized targets with relative ease with both FNs 5.7mm and Hks 4.6mm with any red dot equipped firearm. The optics extend the range far more than barrel length/ gains in velocity.

renatohm said:

...the way I see it, PDW is something a non-rifleman (REMF) uses to fight his way to a rifle, so it has to be somewhat effective up to some 20 meters at most.

I think you have an erroneous understanding of the PDW's real purpose, as well as its necessary range of employment.

PDWs are intended primarily for combat personnel who are not riflemen, such as helicopter pilots and tank crewmen.

Also, the PDW is not meant to enable the user "to fight his way to a rifle."  The PDW is meant to be used in lieu of a rifle.

Armies seem to agree more with 'my' definition - it explains better why dedicated PDW aren't nearly as widespread as pistols and submachine guns for the role.

renatohm said:

Armies seem to agree more with 'my' definition - it explains better why dedicated PDW aren't nearly as widespread as pistols and submachine guns for the role.

It is mostly a matter of no one having made a decent PDW and armies being conservative in regards to retaining 9 mm. The real attempt at PDWs were the P90 and the MP7 and neither have had a lot of success. The AK74u is the closest thing to a proper PDW from that time because it used rifle ammo.

smg762 said:

Like I said the practical hit probability at 300m,  for typical PDW-type personell,  is zero. You could change that by squeezing in a longer 12 inch barrel with reverse feeding.  If you Downsized the caliber,  the saved weight could be spent on an integrated optic with a long 4x zoom.  Then it would be a 300m gun

If we look at how the M16A2 did with trained Infantry soldiers in the ACR rifle trials, it was a 0.3 hit probability at 300m:

Thats a full size rifle with trained infantry shooters, firing not under serious stress (ie no one was trying to kill them.) 

Trying to make a 300m PDW, when full size Assault Rifles are already only 0.3 effective at 300m, seems dubious. Especially when you consider that the PDW equipped soldier has both less training and less shooting-combat experience then a typical rifleman. 

And of course it faces the brutal PDW paradox - the closer the PDW becomes in performance to a rifle, the more it begins to carry like a rifle due to increases in size and weight. At which point, why are they not carrying rifles? Or carrying a rifle caliber PDW (SBR ala Krinkov, etc.)

renatohm said:

Armies seem to agree more with 'my' definition...

Can you name any armies that issue PDWs to cooks, clerks, or other REMFs?

I've seen German tankers with Uzi SMGs, Polish tankers with wz63 SMGs, Russian pilots with APS machine pistols, Dutch pilots with MP9 SMGs, German and American special forces with MP7 SMGs, American pilots with GAU-5A carbines.  All are combat personnel.

I have yet to see cooks or clerks armed with any of those PDWs.

AM I THE ONLY ONE WHO IS INTERESTED IN HOW THIS THING SUPPOSED TO WORKS??

I'm trying to figure out how the internal mechanism works, if the chamber is on top of the magazine then how does the hammer, assuming it was in the bottom of the mag, can reach the firing pin, or does this thing use striker mechanism?

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