If you shoot someone, and the round is not heavy enough to put them down...you need a bigger bullet.
The 5.56 was the old NATO bullet, supposed to create ease of ammo if the Russians came. We’re not in a NATO world anymore, and we’re not fighting Russians.
Was watching Futureweapons the other day, and they were showing a new PDW, shoots the 6.8 caseless round, short barrel, weighs the same as the M-4, highly accurate, much better put-down. If this is out there, why are we wasting time?
Because caseless rounds have a severe problem with removing heat. Cased rounds dump most of the heat into the shell, which is promptly physically ejected. Caseless rounds dump that heat into the chamber, where it disperses slowly. While you can fire mag after mag for hundreds of rounds from a regular design, a caseless system will overheat way too early. H&K had such a design long ago, but they never resolved the heat problem.