The Tracked Self-Propelled 25 pounder, Sexton, was a self propelled artillery gun based on the Canadian Ram medium tank.
The Ram was a medium tank loosely based on the American Medium Tank M3, but with a new upper body and that carried its main gun in a turret. Fifty Ram Is, armed with a 2-pounder gun, and 1,899 Ram IIs, with a 6-pounder gun, were built, but the type was never used in combat.
In 1942 work began on mounting a 25-pounder artillery gun on the chassis of the Ram tank. The normal superstructure and turret was removed, and a boxlike superstructure made out of 0.5-0.75in thick armour replaced it. The 25 pounder was carried just to the left of centre in this open topped structure, with the drive to the front right.
The pilot was completed in late 1942, as the 25 pounder Ram Carrier. It went into production at the Montreal Locomotive Works early in 1943. The name was later changed to the tracked self-propelled 25 pounder, Sexton, following on from the earlier Bishop and the M7 'Priest'.
Early Sextons used the three-piece differential and final drive housing seen on the Medium Tank M3 and early Medium Tank M4s, and the M3 style of Vertical Volute Spring Suspension. During the production run the heavy duty bogies developed for the M3 and the single piece nose introduced on the M4 were used.
The 25 pounder could move 25 degrees left, 15 degrees right, 40 degrees up and 9 degrees down. 112 shells were carried. The Sexton needed a crew of six.
A total of 2,150 Sextons were produced, made up of 124 Sexton Is and 2,026 Sexton IIs, which had a battery and auxiliary generator on the rear deck
The Sexton replaced the M7 Priest in British use, and saw widespread service in Italy and North-Western Europe.