McKinstry had several successes with the
Lurgan-based club
Clan na Gael who he represented at senior level between 1967 and 1985. The side won three
Ulster Club Championship titles in that period, while he was also on the side that lost the
1974 All-Ireland club final to
University College Dublin. McKinstry joined the
Armagh senior football team in 1968 and made his debut in a pre-season tournament involving Armagh,
Antrim,
Dublin and
Sligo. He subsequently established himself on the team where he collected three
Ulster Championships, including one as captain of the side in 1982. McKinstry also lined out at midfield in the
1977 All-Ireland final defeat by Dublin. He received an
All-Star Award in 1980 and also represented
Ulster in the
Railway Cup. McKinstry turned to management after his retirement from playing, beginning with his home club of Clan na Gael. He also had spells in managing the
Middletown and
Tullysaran. ==Death==