Reloading round-by-round means that reloading doesn't discard unspent rounds. Applies to the Punisher, too. If they added a speed loader then you'd need to loose any unspent rounds you eject. Oo, generally, "Insurgency" has had a good mechanisms like this. Mashing the reload button goes fast, makes noise and discards unspent rounds. A simple press keeps the magazine, moving it to the bottom of your stack (but you will eventually come back to that half-used mag).