You really need 3000 fps to produce hydrostatic shock on impact, which makes it an effective round.
That's why there are longer 20-inch barrelled versions. If the extra weight and utility of the grenade launcher isn't needed, the longer and heavier barrel can be fitted, with or without the 100-round double-drum magazine. And barrels can be changed out by a unit armorer or trained squad leader.
But even with the short barrel, it's no worse than a M4 carbine or the Vietnam era 10-inch barrelled XM177s.
I'm impressed with the thing aftrer the 90 rounds I put through one, and oh yeah, it'll have some teething difficulties that'll have to be adderessed. That optical sight ought to have a built-in spare battery, too.
But reworking the handguards should be no problem for a modular weapon design. And hopefully they can be made lighter, too, as long as they're being improved.
