If he served in the regular Army or Navy, enlistment records and muster rolls (or their equivalent) would be available. If he served in a volunteer unit during the War with Spain or the Philippine Insurrection those records would be available. If he later received a pension, those records would be included in the Civil War and later pension files. Some records are available on Ancestry.com and/or Fold3.com, but other records including pension files would only be available at NARA in Washington DC.
Dear Mr. Kinney,
Thank you for posting your request on History Hub!
The nature and location of the service records depends on which branch of service he was in and whether he was an officer or was enlisted.
If he enlisted in the U.S. Navy, we suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and medical records of enlisted men of the U.S. Navy who were separated from the service after 1885 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.
If he was a U.S. Navy officer or served in the U.S. Army or U.S. Marine Corps records regarding his service should be in the custody of the National Archives at Washington, DC - Textual Reference (RDT1).
For a list of record series concerning Army soldiers that served during this time period and, where applicable, links to digitized collections of records, please see the blog post Pre-World War I US Army Service Records. Please note that while some Army records from this time period have been digitized, the majority have not.
In regards to Navy and Marine personnel, we searched the National Archives Catalog and located Abstracts of Service Records of Naval Officers, 5/1798 - 7/1924 in the Records of the Bureau of Naval Personnel (Record Group 24); and Service Records of Enlisted Men, 1798 - ca. 1900 and Alphabetical List of Enlisted Men, 1798 - 1941 in the Records of the U.S. Marine Corps (Record Group 127). Unfortunately, there is not an equivalent series of records for Marine officers for this time period. There are several series that might include information about individual officers, such as Monthly Reports of Details of Officers of the Marine Corps, 1821 - 1911 and various correspondence series in Record Group 127. These records have not been arranged. Therefore, all the records concerning a particular officer are not together. None of these records have been digitized. Another source for Navy and Marine officers is the List of Officers of the Navy of the United States and of the Marine Corps from 1775 to 1900 available online at HathiTrust.
To order copies of service records (except for OMPFs) not already available in the National Archives Catalog, please fill out a NATF Form 86 for the service records and mail the completed form to the address listed on the form. For more information see Requesting Copies of Older (pre-WWI) Military Service Records. There is a reproduction fee for this service.
As Ms. Brooks mentioned, there may also be a pension file for him. Pension files for military personnel who served in the late 19th century may be at either RDT1 or National Archives at St. Louis (RL-SL). Pension files at RDT1 may be ordered using NATF 85. For more information about pension files at RL-SL, please email email@example.com.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1 and RL-SL. Also, all National Archives locations (to include NPRC) have suspended non-emergency reproduction and digitization services until further notice due to COVID-19. Orders will not be serviced until operations can resume safely. NARA has also temporarily suspended the option for placing online orders using eservices.archives.gov. Once operations resume, document reproduction requests will be filled in the order in which they were received. We apologize for any inconvenience.
We hope this information is helpful. Best of luck with your family research!