I didn't actually :)

Radar chronographs becoming smaller although magnetic field MV measurement muzzle device is probably still the most robust and cheap way to measure MV and possibly program Airburst ammo.

Oh, then I'm glad to have shared.

There was also the Advanced Crew Served Weapon (aka the Objective Crew Served Weapon or OCSW), basically a belt-fed grenade machinegun for OICW-like bursting projectiles (25x59 instead of 25x45).  It was supposed to bridge between the Mk19 and the M2.  (Though it was also straight up convertible to fire 12.7x99)

https://en.wikipedia.org/wiki/XM307_Advanced_Crew_Served_Weapon

EmericD said:

Are you really (and seriously) saying that you can't point & shoot a rifle in less than 2 seconds...

???  That is not even remotely close to what I said.

I'm saying that you can't load the grenade, aim with the needed precision at targets beyond point blank range and fire in anywhere near 2 seconds.

Under ideal conditions, it takes 6-8 seconds just to load the grenade and remove the safety clip.  Under combat conditions, expect it to take longer.

EmericD said:

When doing patrol, the point man already loaded the grenade on the rifle, he just need to point the rifle, shoot, and the grenade is airborne.

Right.  How long will it take him to aim carefully enough to hit sufficiently close to a target that is 200-300 meters away?

And that's only one grenade.  For the point man to load and fire another grenade, it will take a lot longer than 2 seconds.

The same time factors are true for the rest of riflemen in the patrol, since they won't have a rifle grenade already loaded.

EmericD said:

       stancrist said: What I said is the video is an example of airburst fragmentation which makes me think the concept could possibly work.

The concept of firing bursts of high power 30 mm AC canon at targets is working, we already know that. It can even defeat tanks. Thinking that an individual weapon could do something remotely similar is, well, wishful thinking.

???  I said nothing about the concept of firing bursts of high power 30mm autocannon ammunition at targets.

I said the video is an example of airburst fragmentation.  I don't know why you're focused on the burst fire.

I would've used this video (https://youtu.be/yuV7Pd4dheI?t=47) of a single 30mm airburst, had I found it earlier.

EmericD said:

       stancrist said: The 30mm cannon airburst videos show fragmentation effect much better than, for example, 40mm grenade airbursts.

Do you mean that the 40 x 53 mm is not effective enough and that we need a more powerful grenade?

No, I mean that the 30mm cannon videos show fragmentation a lot better than that 40mm grenade video.

Perhaps because of the dry, dusty soil, the 30mm fragment strikes are much more visible than the 40mm.

The obvious answer here is a 30mm launcher with mini multi EFP rounds...

I'm not necessarily joking here either. Assuming a modest 5 charge diameter penetration efficiency would allow you to go to 7mm diameter EFP "nodes" which would overwatch the thickest plates and 3a most militaries field. Assuming you got creative with charge packing and used this with a programmable fuzing setup you could reliably kill infantry pretty well with it. 

5 charge diameter penetration efficiency is also likely able to be substantially beaten if you did this right.

OR You could get real cute and creative and make rings of linear cutting charges that don't fire straight out but are instead biased +20-25 and -20-25 degrees along the projectiles outer perimeter AND use AL PTFE exploding charge liners which will not only cut through material but then DETONATE as they run out of steam inside of whatever they hit!

This would likely give you a bare minimum 2-3 meter radius of anything the size of a human being mathematically impossible to avoid taking at least one jet and likely multiple you wouldn't even have to make full bands wrapping the linear cutting charges all the way around the outside of the unit. You could pretty easily calculate up a charge pattern that essentially has a hard no escape zone for humans.

A lot of this may sound like some bizarre far future stuff but darpa and even DOD proper are already working with the technologies you'd need to pull this off.

stancrist said:

I'm saying that you can't load the grenade, aim with the needed precision at targets beyond point blank range and fire in anywhere near 2 seconds.

And that's OK because you don't have to, you're patrolling with the grenade on the rifle, so you can shoot your first shot as fast as you can shoot a rifle (for the lead guy).

stancrist said:

Right.  How long will it take him to aim carefully enough to hit sufficiently close to a target that is 200-300 meters away?

You're not firing rifle grenades in direct fire mode at a distance of 200-300 m. Direct fire mode (firing from the shoulder) is OK for 75-150 m. For 200-300 m, you are going to fire the grenade in indirect fire mode, like a mortar, with the rifle stock on the ground.

It will take more or less the same time than aiming a rifle and expecting a direct hit at the same distance...

You can put a decent amount of HE in a rifle grenade so even if you miss your target by a handful of meters they will take notice.

EmericD said:

       stancrist said: I'm saying that you can't load the grenade, aim with the needed precision at targets beyond point blank range and fire in anywhere near 2 seconds.

And that's OK because you don't have to, you're patrolling with the grenade on the rifle, so you can shoot your first shot as fast as you can shoot a rifle (for the lead guy).

LOL.  So the point man can fire one grenade quickly.  Golly gee wow.

After that one grenade, the point man and all of the rest of the patrol are stuck out in the open, unable to launch any more grenades for another 10-15 seconds.

If riflemen were grenadiers armed with semi-auto grenade launchers, the entire patrol could rain down airburst munitions on the enemy, with effect much like that in the autocannon video.  https://youtu.be/4UolMYY7QaA?t=174

Stll thinking a mix - something like this?

- 1 DMR 

- 1 LMG

- 4 Riflemen with extra belts or grenades

- 2 automagic grenadiers with PDW

DMR and LMG okay, but why so many riflemen?