Let me start by thanking ALL of you for sharing your knowledge
on this topic. I have reached the following conclusions and will
set them down here for you to comment on as to their accuracy.
1) Stock cars were - for the most part - "home road cars" - with respect
to when they were hauling stock from "originating facilities" of stock
loads or moving empty to be loaded. I am talking only about those
situations when they were being loaded by the ranchers and not
about when they were being moved between holding locations.
What I'm saying rather poorly is that if you are talking about a
stock pen on the Santa Fe that the rancher delivers or picks up
his cattle to/from ... then that is probably going to be a car that
is lettered for the ATSF. Not always but usually. Or any other RR
and especially for any Western RR.
2) If you are looking at a "stock train" that is running on any
particular road in the West ... then, again, most of the cars
in that train would be home road cars. But there would
be some cars from neighboring roads and others from
relatively distant roads.
3) Percentages of foreign road cars - for any grouping of cars -
are probably going to be in the 10% to 20% range. Most of
the time. For stock cars in trains in the West.
4) If the train is "somewhere East of the Mississippi" then the
percentages of foreign road cars can go up - especially if you
are talking about a train that is not on a "stock originating
railroad" (or if they don't originate that kind of stock).
5) Stock moves are seasonal in nature and even in the active
season they will be moved in 'clumps' rather than a 'steady
trickle' ... this was a direct result of having to deal with rest,
feed and watering. And there are moves that are not related
to getting the fatted cows to market but rather moving stock
to different ranges, from calf producers to cattle farms, etc.
6) All of the above applies to "the transition era" and might be
considerably different for different eras.
===> So do I get at least a B- grade?