List of British Ordnance Terms - Gunpowder

Gunpowder

Britain employed gunpowder as a propellant until superseded by Cordite Mk I from 1892, and as an explosive filling in common shells until slowly superseded by Lyddite from the late 1890s.

In World War I gunpowder was still in wide British use :

• in shrapnel shells as a burster to propel the bullets out of the case
• in "igniter pads" at the ends of cordite cartridges to facilitate ignition
• as the delay mechanism in time fuzes for artillery
• in vent tubes for firing guns.

British gunpowder designations were :

• E.X.E. : "Extra Experimental" : Propellant : mixture of ⅔ brown and ⅓ black powders, used with BL 6 inch guns Mk III, IV & VI
• L.G. : Large grain : propellant
• Mealed powder : powder in fine dust form : used to ignite fuzes, friction tubes.
• Prism or Molded powders : Propellant pressed into regular hexagonal prism shape, with a hole in the centre to give even burning : included Prism Brown (slower burning) and Prism Black (faster burning).
• P : Pebble powder : Propellant in cube shape, designed to reduce the ratio of surface area to weight, and hence to slow the rate of burning to reduce strain on guns. A larger weight of P (approximately 16% more) is required than R.L.G. for an equivalent charge.
• S.P. : Propellant : P specially selected for consistency, for use in BL guns.
• P Mixture : Mixture of Pebble & Fine Grain powders : Explosive : filled Common & Common-pointed shells.
• Q.F. Mixture : explosive : filled medium sized common & common-pointed shells
• R.F.G.² : Rifle Fine Grain : dogwood charred for 8 hours : bursting charge for Shrapnel & Star shells
• R.L.G. : Rifle Large Grain : Propellant; explosive filling for Armour-piercing shells
• S.B.C. Slow-Burning Cocoa : propellant, brown powder (cocoa refers to the colour).