Could it be that a bullet spends so little time in a barrel once the cartridge is set off that the shooter can't tell if they're feeling maximum acceleration (bullet still in the barrel?) or 'recoil energy'. Maybe, for the shooter to 'feel' recoil, there has to be some acceleration, or force. Wouldn't the gun stop recoiling once the velocity of the 'ejecta' stabilized.
I recall a short article about a Marlin lever gun had six or eight bullets lodged in the barrel. I believe the shooter said he felt no noticable recoil and only heard a low muffled sound every time he pulled the trigger. None of those bullets cleared the muzzle, but if maximum pressure was developed in the chamber or just in front of it, those bullets developed some maximum acceleration and then of course deceleration.
