Dear Ms. Stookey,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located the series titled Command Reports, 1949-1954 in the Records of Adjutant General’s Office (Record Group 407) that includes 5 file units for the 31st Infantry, 7th Infantry Division in 1950. The records are not yet digitized and available in the Catalog. For access to and/or copies, please contact the National Archives at College Park - Textual Reference (RDT2) via email at email@example.com. We were unable to locate specific records of Company M or the 3rd Battalion. Records of lower echelon units sometimes were incorporated into the files of the regiment.
For information regarding U.S. servicemen missing during the Korean War, we suggest you contact the Defense POW/MIA Accounting Agency (DPAA), Public Affairs Office, 2300 Defense Pentagon, ATTN: External Affairs, Washington DC 20301-2300. The web site is https://www.dpaa.mil/
We also suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and individual medical reports for officers of the U.S. Army who were separated from the service after June 1917 and prior to 1956 are in the custody of NARA's National Personnel Records Center in St. Louis. In many cases where personnel records were destroyed in the 1973 fire, proof of service can be provided from other records such as morning reports, payrolls, and military orders, and a certificate of military service will be issued. Please complete a GSA Standard Form 180 and mail it to NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002.
Photographs of various U.S. Army activities dating from 1940 to 2007 are in the custody of the National Archives at College Park - Still Picture (RDSS). Please contact RDSS via email at firstname.lastname@example.org and their web site is https://www.archives.gov/dc-metro/college-park/photographs-Dc.html.
You may wish to review Nightmare at the Chosin Reservoir-National Museum of the United States Army; Battle of Chosin Reservoir; Battle of the Chosin Reservoir: Korean War; and Task Force Faith websites for additional information about this Korean War battle.
We hope this is helpful. Best of luck with your family research!
Thank You Very Much & God Bless
My wife’s uncle was a Sgt in Company M, 3-31. He was KIA on 28, Nov. 1950. We just got his remains home this past year. They were recovered in 2018. If I can be of any assistance please just ask.