And what advantage would such a short barreled rifle offer over a PDW with similar barrel length but an even more compact design?

I think there is a point of dimishing returns.
The idea behind a rifle is accurate fire at ranges in the 300-500 m bracket. For this a certain size and power is needed. Shrinking a rifle down so it doesn't deliver this anymore really puts the concept of a rifle in question.

Msg 615 of 639 to stancriststancrist

In reply toRe: msg 608

From: schnuersi

20-Apr

stancrist said:
Why? Seems somewhat redundant. Also, 84mm HE > 40mm HE.

Because 84 mm are awefully large and heavy. The firing signature is excessive. Such power is not allways needed.
40 mm needs smaller weapons and a larger number can be carried. There are several scenarios in which launching salvos of 40 mm will be more effective than a single 84 mm.

IF a HE based squad structure would become reality IMHO it makes much sense to actually develope optimised weapons for this. Not to rely on legacy designs originally intended for a different purpose.

Msg 616 of 639 to renatohmrenatohm

In reply toRe: msg 600

From: schnuersi

20-Apr

renatohm said:
People have been suggesting just this - more HE, less KE - for some time now.

It also has been more or less a reality in the past.
While most soldiers carried rifles in the past their contribution to a firefight often was rather low. The decicive weapons have been the MG and the HE lobbers. Regardless if in the form of rifle grenades, grenade launchers or light mortars.

During WW2 the main weapons of the German infantry have been the MG, the rifle grenade, the mortar and the light infantry gun. Rifleman/SMgunners only really contributed in close combat situations. In most cases they only provided aditional eyes, ammo carrying capacity and replacement gunners/crews.