GWR 4300 Mogul Class

By 1909 G. J. Churchward's standardisation programme had given the Great Western Railway a powerful express engine in the Saint Class 4-6-0 and a heavy-freight engine in the 2800 Class 2-8-0. What the system lacked was a true mixed-traffic engine, something with the route flexibility to work cross-country lines, secondary main-line expresses, and fast freight without the route-availability restrictions of the larger 4-6-0 designs.

Churchward's answer was a 2-6-0, a wheel arrangement that had been more popular in North America (where it was nicknamed the "Mogul") than in Britain. The first engine, No. 4300, emerged from Swindon Works in May 1911 with a saturated boiler. Production examples followed swiftly, all with superheaters, and the prototype was modified to match. The design shared the boiler, cylinders, motion and Belpaire firebox of Churchward's broader standardisation programme, with new components only where the smaller wheels and 2-6-0 wheel arrangement required them.

Production extended over twenty-one years across five number ranges. The original 4300 batch (1911–1913) was followed by the 5300 batch (1916–1918, including substantial wartime construction for the Railway Operating Department), the 6300 batch (1923–1925), the 7300 batch (1925), and the 9300 batch (1932, originally numbered 8300 and renumbered to 9300 from 1948 onwards as the 8300 numbers were needed elsewhere). Charles Collett, who succeeded Churchward in 1922, introduced detail variations in the later batches, different cabs, footplate arrangements and tender pairings, but the basic design was unchanged for two decades.

During the Second World War the GWR's heavy-freight needs prompted a small batch of Mogul-to-2-8-0 conversions: eight engines were rebuilt with smaller 4-foot 1-inch driving wheels and a redesigned frame to become the 7800 sub-class. After 1945 they were converted back to 2-6-0 form and resumed Mogul numbers.

The Moguls were the GWR's ubiquitous mixed-traffic engine for nearly half a century. They worked secondary expresses on the West Country, North Wales and Welsh Marches main lines, fast goods and fitted-freight workings throughout the system, parcels and milk traffic into Paddington, and seasonal holiday extras to Devon and Cornwall in summer. Their slightly lower axle load gave them access to many cross-country routes, the Cambrian Coast, the Severn & Wye, the Bridport branch, the Tenby coast, that the heavier Saints and Halls could not work.

The class was widely admired for its versatility. Drivers reported that a Mogul would handle anything they were given, with free-running characteristics on faster trains and an ability to lift heavy mineral loads on tight gradients. The combination of long-travel piston valves, generous superheating and a free-steaming boiler gave them an unusually wide power band.

British Railways inherited the entire surviving fleet in 1948 and continued the class on similar duties through the 1950s. The introduction of the BR Standard 4MT 2-6-0 (1953) and the gradual elimination of steam on cross-country routes from 1958 onwards saw the class progressively withdrawn. By the end of 1962 most had gone; the last in regular BR service was No. 6385, withdrawn in November 1964.

One example survived, almost by chance: No. 5322, built in 1917 for War Department service, was sold to Woodham Brothers' scrapyard at Barry in 1965 and bought for preservation in 1969. Restored to working order, it is now the sole survivor of the 342 Moguls built.

Standard GWR taper-boiler outline with two outside cylinders and a 2-6-0 wheel arrangement, distinctly smaller than the Saint and Hall 4-6-0s and lacking their leading bogie. The single-axle pony truck and the smaller Standard No. 4 boiler give the Moguls a more compact appearance. The class wore a GWR Standard pattern cab with two side windows and copper-capped chimney throughout. From the 1930s side window cabs replaced the original Churchward open cabs on most engines. Most Moguls carried the standard GWR Middle Chrome Green livery; numbers were painted on the cabside, with works plates and a standard route classification disc.

4300, the prototype, completed at Swindon in May 1911. Originally fitted with a saturated boiler; subsequently superheated. Withdrawn April 1937 with a remarkable 1,000,000+ miles of running. Not preserved.

5322, built at Swindon in October 1917 for the Railway Operating Department's heavy wartime freight requirements; outshopped in War Department khaki. Returned to GWR ownership after the Armistice. Rescued from Barry scrapyard in 1969, restored to working order, and now resident at the Didcot Railway Centre, the sole surviving Mogul.

7322, first of the post-war "Hawksworth" detail batch, built October 1932, with detail differences in the cab and footplating.

7800-series wartime rebuilds, eight Moguls were rebuilt during the Second World War as 2-8-0 heavy-freight engines, renumbered into the 7800 series. The conversion involved fitting smaller 4-foot 1-inch driving wheels and a redesigned frame; on reversion to peacetime needs they were converted back to Mogul form.

GWR era (1911–1947): from introduction the class was distributed across almost every GWR district. Major Mogul allocations were at Newport Ebbw Junction, Cardiff Canton and Pontypool Road for Welsh Valleys mineral and mixed-traffic work; Old Oak Common in London for parcels and semi-fast services; Bristol St Philip's Marsh and Newton Abbot for West of England trains; Worcester and Tyseley for Birmingham and Welsh Marches duties; and Wolverhampton Stafford Road and Shrewsbury for North Wales and Chester traffic.

British Railways Western Region (1948–1964): the class continued widely distributed across the Western Region. By the early 1960s the survivors were concentrated at the larger Welsh and West Country sheds, Cardiff Canton, Newport Ebbw Junction, Pontypool Road, Severn Tunnel Junction, and Newton Abbot, for the increasingly residual heavy goods and mineral working before final withdrawal in 1964.

GWR pre-war (1911–1939): Middle Chrome Green with black-and-orange lining, polished brass safety-valve casing, copper-capped chimney, and either the GWR roundel or "Great Western" lettering on the tender.

GWR wartime (1940–1947): unlined plain green and (for examples completed during the worst material shortages) plain black with shaded "GWR" tender lettering.

British Railways early (1948–1956): BR mixed-traffic black with red, cream and grey lining; early lion-and-wheel emblem on the tender.

British Railways later (1956–1964): BR lined Brunswick green or unlined black, with the late BR crest. Most Moguls in the latter half of the BR period were turned out unlined.