Dimensions of prototype rail sections

The cross sectional dimensions of prototype flat bottom rails are given in British Standard BS 11, the current issue at the time of writing being 1985. Bull head rails were covered by BS 9 but this has been withdrawn as bullhead rail is now obsolete. The dimensions in the table are those given in the last issue, dated 1935, in which the Reference Number corresponds to the weight in lb/yd.

The bull head section in general use in Britain was 95 lb/yd on main lines and 85 lb/yd on branch lines carrying light traffic. All new track is now laid with 113A flat bottom rails.

The tables list only the overall dimensions of the rail. Prototype dimensions are to the nearest mm. If more detailed information is required refer to the appropriate British Standard.

Bullhead Rails BS 9:1935

BS Reference Number	Height H (mm)		Width W (mm)
	Actual	Scale	Actual	Scale
60	121	2.77	59	1.35
65	124	2.84	60	1.39
70	127	2.92	62	1.42
75	130	2.99	63	1.46
80	136	3.14	65	1.49
85R	139	3.19	68	1.57
90R	141	3.24	70	1.60
95R	145	3.34	70	1.60
100	150	3.45	70	1.60

Flat Bottom Rails BS 11:1985

BS Reference Number	Height H (mm)		Head width Whd (mm)		Foot width Wft (mm)
	Actual	Scale	Actual	Scale	Actual	Scale
50'0'	100	2.30	52	100	1.20	2.30
60A&R	114	2.63	57	110	1.31	2.52
70A	124	2.84	60	111	1.39	2.55
75A	129	2.95	62	114	1.42	2.63
75R	129	2.95	62	122	1.42	2.81
80A	133	3.06	63	117	1.46	2.70
80R	133	3.06	63	127	1.46	2.92
80'0'	127	2.92	63	127	1.46	2.92
90A	143	3.28	67	127	1.53	2.92
90R	143	3.28	67	137	1.53	3.14
95A	148	3.39	70	130	1.60	2.99
95R	148	3.39	68	141	1.57	3.25
95RBH	145	3.34	70	70	1.60	1.60
95N	148	3.39	70	140	1.60	3.21
100A	152	3.50	70	133	1.60	3.06
100R	152	3.50	70	146	1.60	3.35
110A,113A	159	3.65	70	140	1.60	3.21