Prototype Gauge 4'8 1/2" = 1.177083333

NMRA Standard Gauge is min 1.25" to max 1.285" (S-1.2 Standards for Scale Models)

Rail Sizes

Rail Size	Scale Size	Proto Size
Code 55	2.64"	20 lb
Code 70	3.36"	35 lb
Code 83	3.98"	55 lb
Code 100	4.8"	75 lb
Code 125	6.0"	100 lb / 110 lb
Code 148	7.1"	130 lb

O Scale Track Dimensions

References

The O Scale Resource Magazine
Colorado O Scale Modelers
O Scale Trains Magazine
Proto 48

Products

Right-o-way rail, spikes
Midland Products Cork Roadbed 3' (25 pieces)
Woodland Scenics O Scale Products
Woodland Scenics O Scale "Trackbed"
Code 125 rail
Kadee O Scale wheels and trucks
Wiseman Model Services Trucks and other parts