| Power Classification | 6MT |
| Introduced | 1945 – 1947 |
| Designer | Hawksworth |
| Company | GWR |
| Weight – Loco | 76t 17wt |
| Tender | 49t 0cwt |
| Driving Wheels | 6ft 3ins |
| Boiler Pressure | 280psi superheated (reduced to 250psi after fitting double chimney) |
| Cylinders | Outside – 18in x 30in |
| Tractive Effort | 32,580lbf (reduced to 29,090lbf after fitting double chimney) |
| Valve Gear | Stephenson (slide valve) |
These were the ultimate locomotives in the development of the GWR two-cylinder 4-6-0 express engines and were descended directly from the 2900 Saint class. They were the last GWR passenger design built before nationalisation and they were a larger version of the 6959 Modified Hall class but the boiler was based on the LMS 8F 2-8-0 design.
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Modified Hall introduced by Hawksworth in 1944 |
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County introduced by Hawksworth in 1945 |
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LMS 8F introduced by Stanier in 1935 |
They were designed during the war for fast mixed traffic work.
The Counties were distinct from all other GWR 4-6-0 designs in that they had one long splasher covering all the wheels and a straight (instead of curved) nameplate. Every locomotive of the class carried the name of a County served by the GWR (some of which were carried on the previous 4-4-0 County class which were all scrapped in the 1930s). They were never as popular as the other main line classes such as the Halls, as they fell rather uncomfortably between express and mixed traffic classifications.
There were three classes of service for which they were deployed which brought out both the strengths and weaknesses of the locomotives. The Bristol – Paddington runs demanded steady continuous steaming and it was on such duties when trying to make up time that the engines could run short of steam. The Cornish line, with speed restrictions to a maximum of 60mph throughout and heavily graded switchbacks to negotiate also called for very careful handling with engines of such high power and low steaming capacity. The main line from Wolverhampton to Shrewsbury was where the locomotives were most impressive.
From 1956 onwards they were all rebuilt with double chimneys and the boiler pressure was reduced.
The thirty built were all withdrawn between 1962 and 1964 and scrapped. Although there are suggestions that 1011 County of Chester continued in service for a few weeks after its withdrawal in September 1964. One of the last workings for the County of Chester was to haul the 5:45pm 6 coach stopping train from Birmingham Snow Hill to Evesham in September 1964. The locomotive was placed in store in November 1964 and sold to Cashmore’s Scrap yard in Newport where it was cut up in March 1965. No Counties were sent to Woodham Brothers and as a result none were preserved.
Number in Service.
|
Built |
Withdrawals | No. in Service | ||
| BR Numbers |
Quantity |
|||
| 1945 | 1000-1009 | 10 | 10 | |
| 1946 | 1010-1022 | 13 | 23 | |
| 1947 | 1023-1029 | 7 | 30 | |
| 1948-61 | 30 | |||
| 1962 | 9 | 21 | ||
| 1963 | 13 | 8 | ||
| 1964 | 8 | 0 | ||
Allocation of locomotives in service with BR as at 1st of January.
|
1948 |
1954 | 1957 | 1961 | 1962 | 1963 | 1964 | |
| Bristol Bath Road | 7 | 6 | 6 | ||||
| Chester | 4 | 3 | |||||
| Didcot | 4 | ||||||
| Exeter | 1 | 2 | |||||
| Laira (Plymouth) | 3 | 5 | 3 | 3 | 2 | ||
| Newton Abbot | 2 | ||||||
| Neyland | 5 | 4 | 5 | 4 | 4 | ||
| Old Oak Common | 7 | ||||||
| Penzance | 3 | 1 | 3 | 3 | 3 | ||
| Shrewsbury | 5 | 6 | 6 | 6 | 6 | ||
| Stafford Road | 5 | 3 | |||||
| St Phillips Marsh | 9 | 7 | 8 | ||||
| Swindon | 3 | 2 | 4 | 3 | 8 | ||
| Truro | 1 | 1 | 2 | ||||
|
Westbury |
1 |
||||||
| 30 | 30 | 30 | 30 | 30 | 21 | 8 |
Preserved British Steam Locomotives 