QF 6 pounder Nordenfelt

The QF 6 pounder Nordenfelt was a light 57 mm naval gun and coast defence gun of the late 19th century used by many countries.

Note that this gun should not be confused with the short-barreled 57 mm Cockerill-Nordenfelt "Canon de caponnière" or fortification gun, which was used to arm the German A7V tank in World War I.

Nordenfelt guns can be visually differentiated from equivalent and similar Hotchkiss guns by having slimmer barrels than the Hotchkiss, hence the Nordenfelt was considerably lighter.

United Kingdom
The UK adopted a 42-calibres (i.e. 95 inch bore) version as Ordnance QF 6 pounder Nordenfelt Mk I, Mk II, Mk III.

United Kingdom Naval service
They were originally mounted from 1885 onwards for use against the new (steam-driven) torpedo boats which started to enter service in the late 1870s. The Nordenfelt gun was adopted at the same time as the very similar QF 6 pounder Hotchkiss, but the Navy was not satisfied with the special Nordenfelt ammunition and fuzes. Following the explosion in 1900 of an ammunition ship due to defective fuses, Britain replaced Nordenfelt fuzes with the Hotchkiss design. Nordenfelt guns were phased out in favour of the Hotchkiss and were declared obsolete by 1919. 

Ammunition
Diagrams showing the proprietary Nordenfelt 1-inch (top left) and 6-pounder (all others, labelled "2.2 inch") ammunition designs :



Surviving examples

 * A gun at Royal Queensland Yacht Squadron, Manly, Queensland, Australia
 * A gun at the Manege Military Museum, Helsinki, Finland