I had always heard that narrow gauge rail was ordered in 29' lengths to fit on the then standard 30' cars and standard gauge rail was ordered to 39' to fit on the then standard 40' cars. Of course the rail used on today's narrow gauge is mostly stepped down standard gauge stuff so it would be normal for it to be of 39' lengths.
About the chiseling: I've heard it told that if you don't hit the rail just right with the sledge that the steel will 'set' itself and won't break no matter what. Has to be cut. Any truth to that old saw (pun intended
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