I have some Walthers 40’ Ortner cars but I need a different model to build a unit rock train, what are your favourite models?
There is the Walthers 2-bay, Greenville hopper. Also, if you change the trucks on the Walthers Trainline hopper, it is a close representation of some gravel hoppers built in 1970 (http://www.railgoat.railfan.net/spcars/byclass/hopper/h100-23.htm). Those are the only two I can think of off-hand.