4 – loader No 5 – ammunition No 6 – ammunition, normally the "coverer" – second in command and responsible for ammunition preparation and operating the fuze indicator The official "reduced detachment" was four men. Production Many different companies manufactured the guns and component parts in the UK. Vickers-Armstrongs in Scotswood, Baker Perkins in Peterborough and Weirs in Glasgow were some of the most significant. The various Royal Ordnance factories produced most of the ordnance components. In Canada, Sorel Industries built complete guns and provided the ordnance for fitting to the Sexton. Australia also built complete guns, choosing to weld the carriages rather than rivet, as was the practice in the UK and Canada. In all, over 13,000 were made worldwide. Ammunition The 25-pounder fired "separate" or two-part ammunition – the projectile was loaded separately from the propelling charge in its (usually brass) cartridge case with its integral primer. Typically for a quick-firing gun, the cartridge case provided obturation. There were two types of cartridge. The normal cartridge contained three cloth charge bags (coloured red, white and blue). White or blue bags would be removed from the cartridge to give "charge one" or "charge two", leaving all three bags in the cartridge case gave "charge three". The cartridge case was closed at the top with a leatherboard cup. The second type of cartridge was "super", which provided one charge only. The cup could not be removed from the cartridge case. In 1943, an incremental charge of of cordite ("super-plus") was introduced to raise the muzzle velocity when firing armour-piercing shot with charge super; this required a muzzle brake to be fitted. Adoption of "upper-register" (high-angle) fire needed more charges to improve the range overlap. This led to the development of the "intermediate increment" of 4oz cordite, which was introduced in 1944. The bags were striped red and white to indicate that they should only be used with charges one and two. When one bag was used with charge 1 it provided charge 1/2. When one was added to charge 2 it provided charge 2 1/3, and two bags, charge 2 2/3. This allowed a range of seven different charges instead of four. There were many marks of cartridge, mostly differentiated by propellant type. Double-base propellant (nitrocellulose/nitroglycerine) was the UK standard but one mark used US single-base (nitrocellulose only). However, triple-base nitrocellulose/nitroglycerine/picrite was used throughout the war and eventually replaced all