Do you have any additional information on your great grandfather such as place of birth or DOB. Was able to find a Patrick Joseph Mahoney from PA that was in the Navy during WW2 and believed he died while in service. Their is another Joseph Patrick Mahoney from New York? Any additional information may help such as a unit? I believe that the 3rd Marines Regiment was in Cuba at that time in 1922.
Dear Mr. Sowieralski,
Thank you for posting your request on History Hub!
We suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and medical records of officers and enlisted personnel of the U.S. Marine Corps who were separated from service after 1904 and prior to 1958 are located at NARA's National Personnel Records Center (NPRC), (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. To request these records, please mail a completed GSA Standard Form 180 to NPRC. For more information see Official Military Personnel Files (OMPF), Archival Records Requests
Due to the coronavirus public health emergency, the NPRC closed again as of November 7, 2020 until further notice. NPRC will respond only to requests involving burials, medical emergencies, and homeless veterans. If your request is urgent, please see Emergency Requests and Deadlines or emergency requests may be faxed to (314) 801-0764. Please check archives.gov/veterans for updates to the NPRC operating hours and status. We apologize for any inconvenience.
We hope this is helpful. Best of luck with your family research!