The 25pdr SP, tracked, Sexton was a Canadian-designed self-propelled artillery vehicle of the Second World War. It was based on Canadian-built derivatives of the American M3 Lee and M4 Sherman tank chassis. Canada had set up to produce the Ram tank using the M3 chassis and Grizzly (a copy of the M4) to complement US medium tank production; when Sherman production in the US expanded and supply was no longer a problem, it was decided in 1943 to switch the Canadian production lines to produce the Sexton to give the British Army a mobile artillery gun using their 87.6 mm (3.45 in) Ordnance QF 25-pounder gun-howitzer for commonality with towed guns. The Sexton could fire either HE shell or an armour-piercing shell. It found use in the Canadian and British Army, as well as numerous other British Empire and associated forces. Just after the war, a number of Grizzly and Sextons were sold to Portugal, who used them into the 1980s.
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