much of the recent discussion has been on current weapons like the knights KS1 for SF units.

does anyone think there is much scope for new technology, specifically a reduction in ammo size.

for example the G11 ammo was just as small as a pistol round. could you add a case/cartridge (which doesn't add any extra size)

and then add very high pressures,  basically creating a large reduction in ammo size

alternatively, are there new ways to feed cartridges that could reduce size, such as squared, lockless, or triangluar rounds.

which of these came closest to being practical.

or perhaps looking at the magazines, could you somehow have a springless mag, which would allow 40 rounds instead of 30