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Guns? Cannon? Equipments? ... Nomenclature and Terminology |
Some basic terms: BL Once meant 'breech loading'. It now refers to a gun etc in which the propellant charge is contained in a bag of silk or other fabric. Bty battery Calibre refers to the diameter of the bore. In rifled ordnance it is the distance between the two opposite lands. Common ones used on this website are 8-in and 105-mm, referring to 8 inches and 105 millimetres, respectively. Other designations include 25-pr which refers to the mass of the projectile (25 pounds) instead of the calibre. Carronade A short SBML cast iron gun first made by the Carron Ironworks near Falkirk, Scotland, mostly used by the Navy. A number found their way into New Zealand during the Land Wars, some being employed by the Maori. More details. Ballistics The science which deals with the motion of projectiles. Cartridge This contains the propellant charge; it will be in a brass case for QF ordnance or in a cloth or silk bag for BL ordnance. A QF cartridge may be 'fixed' or 'separate' according to whether the brass case is fixed to the projectile or loaded separately. Detonation The molecular breakdown of a substance brought about by shock. Initiated by detonator. Explosion A very rapid combustion of a substance using its own oxygen supply. Initiated by ignition. fs feet per second, a measure of muzzle velocity. Fuze The means of initiating a shell; it may be percussion, or 'point-detonating' (the US definition), graze, time or proximity, ie actuated by a radio signal (Doppler effect) when in proximity to the target. Gunnery The practical application of the science of ballistics. Igniter A small bag of gunpowder sewn on to the end of the BL cartridge. MV Muzzle velocity (usually measured in fs, feet per second). Primer In a QF cartridge the means of ignition screwed into the base of the case. PPS Polygroove Plain Section, a rifling term. QF Once meant 'quick firing'. In ordnance nomenclature it now refers to a piece using a brass cartridge case to contain the propellant charge. RBL Rifled Breech Loading RML Rifled Muzzle Loading SBML Smooth-Bore Muzzle-Loading Shell A shell may be high explosive (HE) when it is filled with a substance, eg TNT, which detonates on being suitably initiated, or it may be a 'carrier' shell, ie designed to carry smoke cannisters, illuminants, propaganda leaflets, chemicals (gas) etc which are ejected by a small charge initiated by a time fuze. Shot A solid projectile used to penetrate armour, etc. SP Self-propelled Splinters or Fragments are pieces of steel into which the body of a HE shell breaks upon detonation and which are meant to inflict casualties. They should not be called 'shrapnel' which became obsolete in 1935. Shrapnel Lead balls of about 12mm diameter once fired from a carrier-type shell against troops in the open. Invented by Lieutenant Henry Shrapnel (1761 - 1842) in 1784. Originally called 'spherical case'. More details. Tube The means of ignition in BL ordnance loaded separately into the breech mechanism. The flash from the tube passes down the vent in the BM and ignites the 'igniter' attached to the cartridge. Windage Windage is generally reckoned as the difference between the diameters of bore and shot; more correctly, it is the difference between their cross-sectional areas.
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