I have no military information regarding your uncle but did find the following Tinson data with a search through Ancestry.com. Hope this is helpful as you pursue details.

Name JOSEPH P TINSON
Birth Date 14 Jul 1900
Death Date 12 Jul 1998
Last Residence Los Angeles, Los Angeles, CA
(City,County,State)
Issued LA (Before 195)
SSN 433-14-0889

California Death Index
TINSON JOSEPH MALE
Birthdate 19 Jan 1922
Deathdate 20 Jan 1944
Place of Birth PENNSYLVANIA
Place of Death SAN DIEGO
Maiden Name of Mother BLAIR
Surname of Father TINSON

1930 Federal census PA
Enumerated in the home of Sadie Taylor as lodgers:
Violet Tinson 27 year old widow with her children
Willema age9
Joseph age 8
Sylvia age 1
Manley age 3 mos

1870 US Federal census
Tinson ,Joseph
Birthplace:
State: Pennsylvania
Age: 5
County: Philadelphia
Gender: Male
Township:
Philadelphia Ward 19 District 61 (2nd Enum)
Race:
Post Office:
Philadelphia
Year: 1870
Roll: M593_1433
Page: 363

The above 5 year old Joseph is enumerated in the household
of 30 year old George and Hannah Tinson. Children listed are
George
Mary
James
Joseph
Millie

Will be glad to send you the images as attachments if you would like.