The M19 40mm Gun Motor Carriage was an anti-aircraft weapon that carried a twin 40mm Bofors gun mount on a modified M24 Light Tank chassis.
The M19 was originally developed using a modified version of the M5A1 Light Tank chassis. This had been developed for the T16 4.5in Gun Motor Carriage, starting in May 1941. The new chassis was lengthened and given a third two-wheeled suspension bogie. The engine was mounted in the middle of the chassis, leaving space for a fighting compartment at the rear.
A whole family of self-propelled weapons, sometimes known as the Light Combat Team, was designed around this chassis. The T65 was produced for the Anti-Aircraft Command and carried a twin 40mm Bofors gun mount on a circular platform at the rear of the vehicle. In February 1943, after successful trials, Anti-Aircraft Command asked for 1,000 T65 40mm Gun Motor Carriages.
Army Ground Forces objected to this order on the grounds that production of the M5 light tank was expected to end fairly soon. Work on the M24 Chaffee began in April 1943, and it was decided to switch most of the light combat team projects from the modified M5A1 to the new M24 chassis. On 25 May 1943 this was done with the T65, which now became the T65E1. This used the same basic design as the T65 with the two Bofors guns carried on a circular mount at the rear of the vehicle, protected by a partial shield.
The prototype was ready early in 1944 and underwent trials at the Aberdeen Proving Ground and the Antiaircraft Artillery Board. A few minor changes were made before the T65E1 was standardized as the M19 40mm Gun Motor Carriage on 14 June 1944. In August an order was placed for 904 M19s, with production split between Cadillac and Massey-Harris.
Only 285 M19s were built before production was cancelled after the end of the Second World War, and even these had their turrets installed post-war. The M19 arrived too late to see service during the Second World War, but it was adopted as the main anti-aircraft vehicle in US Army armoured divisions.
In the late 1940s the M19 was given an electrical generator so that the turret could be powered without the engine running. The modified vehicle was given the designation M19A1 40mm Gun Motor Carriage.
The M19 saw combat during the Korean War. Some were involved in the defence of the Pusan perimeter, where they were used as artillery. Later in the war they were used as infantry support weapons, supporting UN attacks and as a potent defensive weapon, especially during the long periods of positional warfare. Its twin 40mm guns were particularly effective against the Chinese 'human wave' attacks. The M19 was rarely used in the anti-aircraft role, partly because very few North Korean aircraft were encountered and partly because it wasn't really capable of engaging faster moving Chinese jets.
The M19 was used for tests with recoilless rifles. The original plan was to install four T19 105mm recoilless rifles on a M19 GMC chassis, but a shortage of these guns meant that the first test model used four T21 75mm recoilless rifles. These tests demonstrated that the vehicle could quickly fire twenty four rounds in six salvoes against the same target. Tests continued into 1946 with the T19 guns, but the project was then abandoned.
Hull Length: 17ft 11in
Hull Width: 9ft 9.5in
Height: 9ft 4in
Engine: Twin Cadillac V8 petrol engines
Max Speed: 35mph (road)
Max Range: 100-160 miles road radius
Armament: Two 40mm Bofors guns, mounting for one .50in machine gun.