My interest is the post war frontier army. Google Books has many of the prewar Annual Reports of the Secretary of War.
Google Books can be difficult, at times, and ,contrary. The Annual Reports of the Commissary-Subsistence, as well as
the ARQMG can be found, sometimes alone, on GB or as part of the ARSW. Sometimes, contractors can be found in
these annual reports. The antebellum system was somewhat relaxed, compared to the postbellum era. After the war,
stronger, tighter contract specs and descriptions start appearing. For instance, the1889 AM specs, which has been
reprinted of late, has post war specs for currently issued uniforms, camp and garrison equipage, etc., including the
iron pot, mess kettles and mess pans, issued since circa 1808. Take a look, also, at the online NPS book, THESE
RELICS OF BARBARISM; gad, I wish that I had known of this book some 35 years ago!

But, as usual, I digress. Chronic"ling America, the Library of Congress newspaper website, is a gem. Try putting in,
"army pork, salt pork, etc". Or, army contracts". I have found the specs for salt pork (much more specific by the
1870's), beans and the like, including deliveries to I.T. posts, such as Gibson and Towson.

Well, you asked for It! Good luck and I will cover more, at a later date.