List of British Ordnance Terms - QF

QF

QF came from "Quick-firing". The designation was put into use in late 19th century in two different meanings. In naval terms it was first used for small guns firing fixed ammunition i.e. a complete round formed from a metal (brass) cartridge case containing the propellant and projectile in one unit thus enabling higher firing rates. An early example was the QF 6 pounder Hotchkiss. In later pieces, the charge was sometimes separated from the shell to reduce the individual weight of loading, but the charge was still loaded in a brass case, rather than a cloth or silk bag typical of "BL" guns.

In formal British ordnance terminology the term QF came to mean that the propellant charge is loaded in a metal, usually brass, case which provides obturation i.e. seals the breech to prevent escape of the expanding propellant gas. The term QF hence referred to both the breech-sealing mechanism and the method of loading propellant charges. Ordnance of other countries employed other techniques, and hence this description and distinction is limited to British ordnance.

Following the early success of the light QF Hotchkiss and Nordenfelt guns in the 1880s, the Royal Navy implemented QF guns in all calibres up to 6 inch in the 1890s, and also converted various 4 inch and 6 inch BL guns to QF under the designation QFC. This all-QF era ended in 1901 with the BL 6 inch Mk VII gun and a swing back to BL guns. Since 1914 the trend has been to use QF for naval guns below 6 inch and BL for guns 6 inch and over.