FV433 Abbot SPG
FV433 Field Artillery, Self-Propelled "Abbot" is the self-propelled artillery variant of the British Army FV430 series of armoured fighting vehicles, using much of the chassis of the FV430 but with a fully rotating turret at the rear housing the 105 mm gun and given the vehicle designation of FV433.
Its correct designation was "Gun Equipment 105mm L109 (Abbot)"; L109 was little used, probably to avoid confusion with 155 mm M109 that entered UK service at about the same time. The name "Abbot" continued the Second World War style of naming self-propelled artillery after ecclesiastical titles. The FV433 used a different configuration of power pack from other vehicles in the FV430 series.
Development
Ammunition
A completely new ammunition family, comprising shells, fuzes and cartridges, was designed for Abbot, designated 105 mm Field (105 mm Fd), was designed for Abbot's L13 ordnance. It uses electrical instead of percussion primers, and compared to US 105 mm M1 type ammunition has longer shells. The widely used US M1 type round was called "105 mm How" in UK service. The 105 mm Fd came in two marks, both separate loading (shell and cartridge loaded separately). The 105 mm Fd Mk 1 was used initially, it had a UK-produced 105 mm How shell, mostly US pattern fuzes and reduced charge 105 mm Fd cartridges with their electrical primers (105 mm M1 uses percussion primers).