Grange first saw significant combat action as a second lieutenant assigned to the 101st Airborne's "Lima" Ranger company in the I Corps Tactical Zone of Vietnam in 1970.

In 1981 Grange completed the grueling British SAS Course at Hereford, England, then attended the Marine Corps Command and Staff College.

After his selection as a general officer, he served as both ADC for support and maneuver in the 3rd Infantry Division at Warner Barracks in Bamberg, Germany.

He then led a group of Army officers who wrote a book on improving force structure; Air-Mech-Strike: Asymmetric Maneuver Warfare for the 21st Century.

[8] Grange provided information operations expertise and "ground truth" geopolitical consultancy to Senior Executives in both public and private sectors.

The expeditionary security assessments were conducted throughout the Middle East, North Africa and Asia Pacific Rim, providing critical strategic value to public and private sector decision makers.

During the Libyan Civil War (2011–present) Osprey Global Solutions sought to build field hospitals in Libya and train the country's national police after the fall of Muammar el-Qaddafi.

In 2015, national news reporting on the Secretary of State Hillary Clinton's 2012 email controversy highlighted that Grange was requested by private sector executives to provide his subject matter expertise for Libya.