If you're drilling down that far into production dates, consider the available models and what they represent. There were variations between batches and the model you have may only be close for certain timeframes. Tangent says their car represents 1968 and 1970 prototypes, and who knows what the Athearn tooling is supposed to be, but it was first advertised in 1971.
Rob Spangler
I do not have the info in front of me, but IIRC - 1966-1972(Sept). The problem is that the transition from the 4740 to the 4750 car is not smooth. PS built 'kits' and a number of railroads(and other car builders) built those kits(and built un-licensed 'clones') of the PS designs through the years.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."
The subject line should give enough of a description: What are the exact production dates for the PS-2CD 4740 cu ft covered hoppers? I know from general searches, it started in 1966 and ended in 1972. The problem is I can't seem to find when in 1972 the last 4740 hopper was produced. I am freelancing a railroad that uses the 4740 hoppers and the came into existance in 1972. I am planning custom decals for the cars and I want to be right with the build dates. Any info anyone can provide would be very welcome.