The term did not mean that the weapon was automatic. The QF 3-pounder Hotchkiss and manually loaded 4.7-inch guns show that the Royal Navy applied the label to weapons designed for faster handling and repeat fire. Features could include cased ammunition and breech arrangements that sped manual loading. The designation belongs to the standards of its period, so modern readers should not treat "quick-firing" as a synonym for automatic cannon.
Notable Point · 1:30:14-1:33:11
Why “quick-firing” did not mean automatic
The Royal Navy's quick-firing label described period loading and handling standards, not an automatic weapon in the modern sense.