>>63972183
I have a vague idea of it, but I really never understood why both barrels share one bolt carrier, and you could definitely NOT fit very much explosives in a .50 caliber projectile.

>>63972660
Because the M320 isn't a proper underbarrel launcher, it's a standalone launcher which can be attached onto a rail if you want, making it ungainly and bulky as fuck, defeating the whole point of an underbarrel launcher.